diff --git a/Emby.Server.Implementations/AppBase/BaseApplicationPaths.cs b/Emby.Server.Implementations/AppBase/BaseApplicationPaths.cs
index 660bbb2deb..6edfad575a 100644
--- a/Emby.Server.Implementations/AppBase/BaseApplicationPaths.cs
+++ b/Emby.Server.Implementations/AppBase/BaseApplicationPaths.cs
@@ -33,7 +33,7 @@ namespace Emby.Server.Implementations.AppBase
             CachePath = cacheDirectoryPath;
             WebPath = webDirectoryPath;
 
-            DataPath = Path.Combine(ProgramDataPath, "data");
+            _dataPath = Directory.CreateDirectory(Path.Combine(ProgramDataPath, "data")).FullName;
         }
 
         /// <summary>
@@ -55,11 +55,7 @@ namespace Emby.Server.Implementations.AppBase
         /// Gets the folder path to the data directory.
         /// </summary>
         /// <value>The data directory.</value>
-        public string DataPath
-        {
-            get => _dataPath;
-            private set => _dataPath = Directory.CreateDirectory(value).FullName;
-        }
+        public string DataPath => _dataPath;
 
         /// <inheritdoc />
         public string VirtualDataPath => "%AppDataPath%";
diff --git a/Emby.Server.Implementations/AppBase/BaseConfigurationManager.cs b/Emby.Server.Implementations/AppBase/BaseConfigurationManager.cs
index 4f72c8ce15..8c919db431 100644
--- a/Emby.Server.Implementations/AppBase/BaseConfigurationManager.cs
+++ b/Emby.Server.Implementations/AppBase/BaseConfigurationManager.cs
@@ -1,3 +1,5 @@
+#nullable disable
+
 using System;
 using System.Collections.Concurrent;
 using System.Collections.Generic;
diff --git a/Emby.Server.Implementations/AppBase/ConfigurationHelper.cs b/Emby.Server.Implementations/AppBase/ConfigurationHelper.cs
index 29bac66340..de770f59ec 100644
--- a/Emby.Server.Implementations/AppBase/ConfigurationHelper.cs
+++ b/Emby.Server.Implementations/AppBase/ConfigurationHelper.cs
@@ -1,5 +1,3 @@
-#nullable enable
-
 using System;
 using System.IO;
 using System.Linq;
diff --git a/Emby.Server.Implementations/ApplicationHost.cs b/Emby.Server.Implementations/ApplicationHost.cs
index 75d8fc113d..82995deb30 100644
--- a/Emby.Server.Implementations/ApplicationHost.cs
+++ b/Emby.Server.Implementations/ApplicationHost.cs
@@ -1,3 +1,5 @@
+#nullable disable
+
 #pragma warning disable CS1591
 
 using System;
diff --git a/Emby.Server.Implementations/Channels/ChannelManager.cs b/Emby.Server.Implementations/Channels/ChannelManager.cs
index 7324b0ee9f..448f124034 100644
--- a/Emby.Server.Implementations/Channels/ChannelManager.cs
+++ b/Emby.Server.Implementations/Channels/ChannelManager.cs
@@ -1,3 +1,5 @@
+#nullable disable
+
 using System;
 using System.Collections.Generic;
 using System.Globalization;
diff --git a/Emby.Server.Implementations/Collections/CollectionImageProvider.cs b/Emby.Server.Implementations/Collections/CollectionImageProvider.cs
index c69a07e83e..ca84094024 100644
--- a/Emby.Server.Implementations/Collections/CollectionImageProvider.cs
+++ b/Emby.Server.Implementations/Collections/CollectionImageProvider.cs
@@ -82,9 +82,9 @@ namespace Emby.Server.Implementations.Collections
                     return null;
                 })
                 .Where(i => i != null)
-                .GroupBy(x => x.Id)
+                .GroupBy(x => x!.Id) // We removed the null values
                 .Select(x => x.First())
-                .ToList();
+                .ToList()!; // Again... the list doesn't contain any null values
         }
 
         /// <inheritdoc />
diff --git a/Emby.Server.Implementations/Collections/CollectionManager.cs b/Emby.Server.Implementations/Collections/CollectionManager.cs
index c56f334481..82d80fc83c 100644
--- a/Emby.Server.Implementations/Collections/CollectionManager.cs
+++ b/Emby.Server.Implementations/Collections/CollectionManager.cs
@@ -1,3 +1,5 @@
+#nullable disable
+
 using System;
 using System.Collections.Generic;
 using System.IO;
diff --git a/Emby.Server.Implementations/Configuration/ServerConfigurationManager.cs b/Emby.Server.Implementations/Configuration/ServerConfigurationManager.cs
index 7a8ed8c29f..ff5602f243 100644
--- a/Emby.Server.Implementations/Configuration/ServerConfigurationManager.cs
+++ b/Emby.Server.Implementations/Configuration/ServerConfigurationManager.cs
@@ -1,3 +1,5 @@
+#nullable disable
+
 using System;
 using System.Globalization;
 using System.IO;
diff --git a/Emby.Server.Implementations/Cryptography/CryptographyProvider.cs b/Emby.Server.Implementations/Cryptography/CryptographyProvider.cs
index 12a9e44e70..4a9b280852 100644
--- a/Emby.Server.Implementations/Cryptography/CryptographyProvider.cs
+++ b/Emby.Server.Implementations/Cryptography/CryptographyProvider.cs
@@ -1,5 +1,3 @@
-#nullable enable
-
 using System;
 using System.Collections.Generic;
 using System.Security.Cryptography;
diff --git a/Emby.Server.Implementations/Data/BaseSqliteRepository.cs b/Emby.Server.Implementations/Data/BaseSqliteRepository.cs
index c331a61124..6f23a0888e 100644
--- a/Emby.Server.Implementations/Data/BaseSqliteRepository.cs
+++ b/Emby.Server.Implementations/Data/BaseSqliteRepository.cs
@@ -1,3 +1,5 @@
+#nullable disable
+
 #pragma warning disable CS1591
 
 using System;
diff --git a/Emby.Server.Implementations/Data/ManagedConnection.cs b/Emby.Server.Implementations/Data/ManagedConnection.cs
index 5c094ddd2d..10c6f837e6 100644
--- a/Emby.Server.Implementations/Data/ManagedConnection.cs
+++ b/Emby.Server.Implementations/Data/ManagedConnection.cs
@@ -9,7 +9,7 @@ namespace Emby.Server.Implementations.Data
 {
     public class ManagedConnection : IDisposable
     {
-        private SQLiteDatabaseConnection _db;
+        private SQLiteDatabaseConnection? _db;
         private readonly SemaphoreSlim _writeLock;
         private bool _disposed = false;
 
diff --git a/Emby.Server.Implementations/Data/SqliteExtensions.cs b/Emby.Server.Implementations/Data/SqliteExtensions.cs
index a8f3feb589..e532825af5 100644
--- a/Emby.Server.Implementations/Data/SqliteExtensions.cs
+++ b/Emby.Server.Implementations/Data/SqliteExtensions.cs
@@ -1,3 +1,4 @@
+#nullable disable
 #pragma warning disable CS1591
 
 using System;
diff --git a/Emby.Server.Implementations/Data/SqliteItemRepository.cs b/Emby.Server.Implementations/Data/SqliteItemRepository.cs
index b3d8860a9e..5b4bbb3395 100644
--- a/Emby.Server.Implementations/Data/SqliteItemRepository.cs
+++ b/Emby.Server.Implementations/Data/SqliteItemRepository.cs
@@ -1,3 +1,5 @@
+#nullable disable
+
 #pragma warning disable CS1591
 
 using System;
diff --git a/Emby.Server.Implementations/Data/SqliteUserDataRepository.cs b/Emby.Server.Implementations/Data/SqliteUserDataRepository.cs
index e0ebd0a6cf..1756bcae08 100644
--- a/Emby.Server.Implementations/Data/SqliteUserDataRepository.cs
+++ b/Emby.Server.Implementations/Data/SqliteUserDataRepository.cs
@@ -1,3 +1,5 @@
+#nullable disable
+
 #pragma warning disable CS1591
 
 using System;
diff --git a/Emby.Server.Implementations/Data/TypeMapper.cs b/Emby.Server.Implementations/Data/TypeMapper.cs
index 7044b1d194..7f1306d15a 100644
--- a/Emby.Server.Implementations/Data/TypeMapper.cs
+++ b/Emby.Server.Implementations/Data/TypeMapper.cs
@@ -13,7 +13,7 @@ namespace Emby.Server.Implementations.Data
         /// This holds all the types in the running assemblies
         /// so that we can de-serialize properly when we don't have strong types.
         /// </summary>
-        private readonly ConcurrentDictionary<string, Type> _typeMap = new ConcurrentDictionary<string, Type>();
+        private readonly ConcurrentDictionary<string, Type?> _typeMap = new ConcurrentDictionary<string, Type?>();
 
         /// <summary>
         /// Gets the type.
@@ -21,7 +21,7 @@ namespace Emby.Server.Implementations.Data
         /// <param name="typeName">Name of the type.</param>
         /// <returns>Type.</returns>
         /// <exception cref="ArgumentNullException"><c>typeName</c> is null.</exception>
-        public Type GetType(string typeName)
+        public Type? GetType(string typeName)
         {
             if (string.IsNullOrEmpty(typeName))
             {
@@ -36,7 +36,7 @@ namespace Emby.Server.Implementations.Data
         /// </summary>
         /// <param name="typeName">Name of the type.</param>
         /// <returns>Type.</returns>
-        private Type LookupType(string typeName)
+        private Type? LookupType(string typeName)
         {
             return AppDomain.CurrentDomain.GetAssemblies()
                 .Select(a => a.GetType(typeName))
diff --git a/Emby.Server.Implementations/Devices/DeviceId.cs b/Emby.Server.Implementations/Devices/DeviceId.cs
index fa6ac95fd3..3d15b3e768 100644
--- a/Emby.Server.Implementations/Devices/DeviceId.cs
+++ b/Emby.Server.Implementations/Devices/DeviceId.cs
@@ -1,3 +1,5 @@
+#nullable disable
+
 #pragma warning disable CS1591
 
 using System;
diff --git a/Emby.Server.Implementations/Devices/DeviceManager.cs b/Emby.Server.Implementations/Devices/DeviceManager.cs
index da5047d244..2637addce7 100644
--- a/Emby.Server.Implementations/Devices/DeviceManager.cs
+++ b/Emby.Server.Implementations/Devices/DeviceManager.cs
@@ -1,3 +1,5 @@
+#nullable disable
+
 #pragma warning disable CS1591
 
 using System;
diff --git a/Emby.Server.Implementations/Dto/DtoService.cs b/Emby.Server.Implementations/Dto/DtoService.cs
index 4ae35039ab..7411239a1e 100644
--- a/Emby.Server.Implementations/Dto/DtoService.cs
+++ b/Emby.Server.Implementations/Dto/DtoService.cs
@@ -1,3 +1,5 @@
+#nullable disable
+
 #pragma warning disable CS1591
 
 using System;
diff --git a/Emby.Server.Implementations/Emby.Server.Implementations.csproj b/Emby.Server.Implementations/Emby.Server.Implementations.csproj
index 14f6f565c4..113863519b 100644
--- a/Emby.Server.Implementations/Emby.Server.Implementations.csproj
+++ b/Emby.Server.Implementations/Emby.Server.Implementations.csproj
@@ -44,6 +44,7 @@
     <GenerateAssemblyInfo>false</GenerateAssemblyInfo>
     <GenerateDocumentationFile>true</GenerateDocumentationFile>
     <TreatWarningsAsErrors Condition=" '$(Configuration)' == 'Release'">true</TreatWarningsAsErrors>
+    <Nullable>enable</Nullable>
     <!-- https://github.com/microsoft/ApplicationInsights-dotnet/issues/2047 -->
     <NoWarn>AD0001</NoWarn>
     <AnalysisMode Condition=" '$(Configuration)' == 'Debug' ">AllEnabledByDefault</AnalysisMode>
diff --git a/Emby.Server.Implementations/EntryPoints/ExternalPortForwarding.cs b/Emby.Server.Implementations/EntryPoints/ExternalPortForwarding.cs
index 14201ead29..cc3e4a2c24 100644
--- a/Emby.Server.Implementations/EntryPoints/ExternalPortForwarding.cs
+++ b/Emby.Server.Implementations/EntryPoints/ExternalPortForwarding.cs
@@ -1,3 +1,5 @@
+#nullable disable
+
 #pragma warning disable CS1591
 
 using System;
diff --git a/Emby.Server.Implementations/EntryPoints/LibraryChangedNotifier.cs b/Emby.Server.Implementations/EntryPoints/LibraryChangedNotifier.cs
index ae1b51b4c3..5bb4100ba9 100644
--- a/Emby.Server.Implementations/EntryPoints/LibraryChangedNotifier.cs
+++ b/Emby.Server.Implementations/EntryPoints/LibraryChangedNotifier.cs
@@ -1,3 +1,5 @@
+#nullable disable
+
 #pragma warning disable CS1591
 
 using System;
diff --git a/Emby.Server.Implementations/EntryPoints/RecordingNotifier.cs b/Emby.Server.Implementations/EntryPoints/RecordingNotifier.cs
index 824bb85f44..e0ca02d986 100644
--- a/Emby.Server.Implementations/EntryPoints/RecordingNotifier.cs
+++ b/Emby.Server.Implementations/EntryPoints/RecordingNotifier.cs
@@ -1,3 +1,5 @@
+#nullable disable
+
 #pragma warning disable CS1591
 
 using System;
diff --git a/Emby.Server.Implementations/EntryPoints/UdpServerEntryPoint.cs b/Emby.Server.Implementations/EntryPoints/UdpServerEntryPoint.cs
index 3624e079f5..211941f443 100644
--- a/Emby.Server.Implementations/EntryPoints/UdpServerEntryPoint.cs
+++ b/Emby.Server.Implementations/EntryPoints/UdpServerEntryPoint.cs
@@ -1,5 +1,3 @@
-#nullable enable
-
 using System;
 using System.Net.Sockets;
 using System.Threading;
diff --git a/Emby.Server.Implementations/EntryPoints/UserDataChangeNotifier.cs b/Emby.Server.Implementations/EntryPoints/UserDataChangeNotifier.cs
index 1989e9ed25..332fb33858 100644
--- a/Emby.Server.Implementations/EntryPoints/UserDataChangeNotifier.cs
+++ b/Emby.Server.Implementations/EntryPoints/UserDataChangeNotifier.cs
@@ -1,3 +1,5 @@
+#nullable disable
+
 #pragma warning disable CS1591
 
 using System;
diff --git a/Emby.Server.Implementations/HttpServer/Security/AuthorizationContext.cs b/Emby.Server.Implementations/HttpServer/Security/AuthorizationContext.cs
index fbf9254d16..c87f7dbbde 100644
--- a/Emby.Server.Implementations/HttpServer/Security/AuthorizationContext.cs
+++ b/Emby.Server.Implementations/HttpServer/Security/AuthorizationContext.cs
@@ -27,7 +27,7 @@ namespace Emby.Server.Implementations.HttpServer.Security
         {
             if (requestContext.Request.HttpContext.Items.TryGetValue("AuthorizationInfo", out var cached))
             {
-                return (AuthorizationInfo)cached;
+                return (AuthorizationInfo)cached!; // Cache should never contain null
             }
 
             return GetAuthorization(requestContext);
@@ -55,15 +55,15 @@ namespace Emby.Server.Implementations.HttpServer.Security
         }
 
         private AuthorizationInfo GetAuthorizationInfoFromDictionary(
-            in Dictionary<string, string> auth,
+            in Dictionary<string, string>? auth,
             in IHeaderDictionary headers,
             in IQueryCollection queryString)
         {
-            string deviceId = null;
-            string device = null;
-            string client = null;
-            string version = null;
-            string token = null;
+            string? deviceId = null;
+            string? device = null;
+            string? client = null;
+            string? version = null;
+            string? token = null;
 
             if (auth != null)
             {
@@ -206,7 +206,7 @@ namespace Emby.Server.Implementations.HttpServer.Security
         /// </summary>
         /// <param name="httpReq">The HTTP req.</param>
         /// <returns>Dictionary{System.StringSystem.String}.</returns>
-        private Dictionary<string, string> GetAuthorizationDictionary(HttpContext httpReq)
+        private Dictionary<string, string>? GetAuthorizationDictionary(HttpContext httpReq)
         {
             var auth = httpReq.Request.Headers["X-Emby-Authorization"];
 
@@ -223,7 +223,7 @@ namespace Emby.Server.Implementations.HttpServer.Security
         /// </summary>
         /// <param name="httpReq">The HTTP req.</param>
         /// <returns>Dictionary{System.StringSystem.String}.</returns>
-        private Dictionary<string, string> GetAuthorizationDictionary(HttpRequest httpReq)
+        private Dictionary<string, string>? GetAuthorizationDictionary(HttpRequest httpReq)
         {
             var auth = httpReq.Headers["X-Emby-Authorization"];
 
@@ -240,7 +240,7 @@ namespace Emby.Server.Implementations.HttpServer.Security
         /// </summary>
         /// <param name="authorizationHeader">The authorization header.</param>
         /// <returns>Dictionary{System.StringSystem.String}.</returns>
-        private Dictionary<string, string> GetAuthorization(ReadOnlySpan<char> authorizationHeader)
+        private Dictionary<string, string>? GetAuthorization(ReadOnlySpan<char> authorizationHeader)
         {
             if (authorizationHeader == null)
             {
diff --git a/Emby.Server.Implementations/HttpServer/Security/SessionContext.cs b/Emby.Server.Implementations/HttpServer/Security/SessionContext.cs
index dd77b45d89..c375f36ce4 100644
--- a/Emby.Server.Implementations/HttpServer/Security/SessionContext.cs
+++ b/Emby.Server.Implementations/HttpServer/Security/SessionContext.cs
@@ -36,14 +36,14 @@ namespace Emby.Server.Implementations.HttpServer.Security
             return GetSession((HttpContext)requestContext);
         }
 
-        public User GetUser(HttpContext requestContext)
+        public User? GetUser(HttpContext requestContext)
         {
             var session = GetSession(requestContext);
 
             return session == null || session.UserId.Equals(Guid.Empty) ? null : _userManager.GetUserById(session.UserId);
         }
 
-        public User GetUser(object requestContext)
+        public User? GetUser(object requestContext)
         {
             return GetUser(((HttpRequest)requestContext).HttpContext);
         }
diff --git a/Emby.Server.Implementations/HttpServer/WebSocketConnection.cs b/Emby.Server.Implementations/HttpServer/WebSocketConnection.cs
index 06acb56061..8f7d606692 100644
--- a/Emby.Server.Implementations/HttpServer/WebSocketConnection.cs
+++ b/Emby.Server.Implementations/HttpServer/WebSocketConnection.cs
@@ -1,5 +1,3 @@
-#nullable enable
-
 using System;
 using System.Buffers;
 using System.IO.Pipelines;
diff --git a/Emby.Server.Implementations/HttpServer/WebSocketManager.cs b/Emby.Server.Implementations/HttpServer/WebSocketManager.cs
index 1bee1ac310..861c0a95e3 100644
--- a/Emby.Server.Implementations/HttpServer/WebSocketManager.cs
+++ b/Emby.Server.Implementations/HttpServer/WebSocketManager.cs
@@ -1,3 +1,5 @@
+#nullable disable
+
 #pragma warning disable CS1591
 
 using System;
diff --git a/Emby.Server.Implementations/IO/FileRefresher.cs b/Emby.Server.Implementations/IO/FileRefresher.cs
index 7435e9d0bf..47a83d77ce 100644
--- a/Emby.Server.Implementations/IO/FileRefresher.cs
+++ b/Emby.Server.Implementations/IO/FileRefresher.cs
@@ -1,3 +1,5 @@
+#nullable disable
+
 #pragma warning disable CS1591
 
 using System;
diff --git a/Emby.Server.Implementations/IO/LibraryMonitor.cs b/Emby.Server.Implementations/IO/LibraryMonitor.cs
index 3353fae9d8..aa80bccd72 100644
--- a/Emby.Server.Implementations/IO/LibraryMonitor.cs
+++ b/Emby.Server.Implementations/IO/LibraryMonitor.cs
@@ -1,3 +1,5 @@
+#nullable disable
+
 #pragma warning disable CS1591
 
 using System;
diff --git a/Emby.Server.Implementations/IO/ManagedFileSystem.cs b/Emby.Server.Implementations/IO/ManagedFileSystem.cs
index 27096ed334..6a554e68ab 100644
--- a/Emby.Server.Implementations/IO/ManagedFileSystem.cs
+++ b/Emby.Server.Implementations/IO/ManagedFileSystem.cs
@@ -61,7 +61,7 @@ namespace Emby.Server.Implementations.IO
         /// <param name="filename">The filename.</param>
         /// <returns>System.String.</returns>
         /// <exception cref="ArgumentNullException">filename</exception>
-        public virtual string ResolveShortcut(string filename)
+        public virtual string? ResolveShortcut(string filename)
         {
             if (string.IsNullOrEmpty(filename))
             {
@@ -601,7 +601,7 @@ namespace Emby.Server.Implementations.IO
             return GetFiles(path, null, false, recursive);
         }
 
-        public virtual IEnumerable<FileSystemMetadata> GetFiles(string path, IReadOnlyList<string> extensions, bool enableCaseSensitiveExtensions, bool recursive = false)
+        public virtual IEnumerable<FileSystemMetadata> GetFiles(string path, IReadOnlyList<string>? extensions, bool enableCaseSensitiveExtensions, bool recursive = false)
         {
             var enumerationOptions = GetEnumerationOptions(recursive);
 
@@ -655,7 +655,7 @@ namespace Emby.Server.Implementations.IO
             return GetFilePaths(path, null, false, recursive);
         }
 
-        public virtual IEnumerable<string> GetFilePaths(string path, string[] extensions, bool enableCaseSensitiveExtensions, bool recursive = false)
+        public virtual IEnumerable<string> GetFilePaths(string path, string[]? extensions, bool enableCaseSensitiveExtensions, bool recursive = false)
         {
             var enumerationOptions = GetEnumerationOptions(recursive);
 
diff --git a/Emby.Server.Implementations/IO/MbLinkShortcutHandler.cs b/Emby.Server.Implementations/IO/MbLinkShortcutHandler.cs
index e6696b8c4c..76c58d5dcd 100644
--- a/Emby.Server.Implementations/IO/MbLinkShortcutHandler.cs
+++ b/Emby.Server.Implementations/IO/MbLinkShortcutHandler.cs
@@ -17,7 +17,7 @@ namespace Emby.Server.Implementations.IO
 
         public string Extension => ".mblink";
 
-        public string Resolve(string shortcutPath)
+        public string? Resolve(string shortcutPath)
         {
             if (string.IsNullOrEmpty(shortcutPath))
             {
diff --git a/Emby.Server.Implementations/IO/StreamHelper.cs b/Emby.Server.Implementations/IO/StreamHelper.cs
index c16ebd61b7..e4f5f4cf0b 100644
--- a/Emby.Server.Implementations/IO/StreamHelper.cs
+++ b/Emby.Server.Implementations/IO/StreamHelper.cs
@@ -11,7 +11,7 @@ namespace Emby.Server.Implementations.IO
 {
     public class StreamHelper : IStreamHelper
     {
-        public async Task CopyToAsync(Stream source, Stream destination, int bufferSize, Action onStarted, CancellationToken cancellationToken)
+        public async Task CopyToAsync(Stream source, Stream destination, int bufferSize, Action? onStarted, CancellationToken cancellationToken)
         {
             byte[] buffer = ArrayPool<byte>.Shared.Rent(bufferSize);
             try
diff --git a/Emby.Server.Implementations/IStartupOptions.cs b/Emby.Server.Implementations/IStartupOptions.cs
index f719dc5f89..a430b9e720 100644
--- a/Emby.Server.Implementations/IStartupOptions.cs
+++ b/Emby.Server.Implementations/IStartupOptions.cs
@@ -1,5 +1,4 @@
 #pragma warning disable CS1591
-#nullable enable
 
 namespace Emby.Server.Implementations
 {
diff --git a/Emby.Server.Implementations/Images/BaseDynamicImageProvider.cs b/Emby.Server.Implementations/Images/BaseDynamicImageProvider.cs
index 6fa3c1c618..833fb0b7a1 100644
--- a/Emby.Server.Implementations/Images/BaseDynamicImageProvider.cs
+++ b/Emby.Server.Implementations/Images/BaseDynamicImageProvider.cs
@@ -1,3 +1,5 @@
+#nullable disable
+
 #pragma warning disable CS1591
 
 using System;
diff --git a/Emby.Server.Implementations/Images/CollectionFolderImageProvider.cs b/Emby.Server.Implementations/Images/CollectionFolderImageProvider.cs
index 161b4c4528..ff5f26ce09 100644
--- a/Emby.Server.Implementations/Images/CollectionFolderImageProvider.cs
+++ b/Emby.Server.Implementations/Images/CollectionFolderImageProvider.cs
@@ -1,3 +1,5 @@
+#nullable disable
+
 #pragma warning disable CS1591
 
 using System;
diff --git a/Emby.Server.Implementations/Images/DynamicImageProvider.cs b/Emby.Server.Implementations/Images/DynamicImageProvider.cs
index 50c5314820..900b3fd9c6 100644
--- a/Emby.Server.Implementations/Images/DynamicImageProvider.cs
+++ b/Emby.Server.Implementations/Images/DynamicImageProvider.cs
@@ -1,3 +1,5 @@
+#nullable disable
+
 #pragma warning disable CS1591
 
 using System;
diff --git a/Emby.Server.Implementations/Images/FolderImageProvider.cs b/Emby.Server.Implementations/Images/FolderImageProvider.cs
index 0224ab32a0..859017f869 100644
--- a/Emby.Server.Implementations/Images/FolderImageProvider.cs
+++ b/Emby.Server.Implementations/Images/FolderImageProvider.cs
@@ -1,3 +1,5 @@
+#nullable disable
+
 #pragma warning disable CS1591
 
 using System.Collections.Generic;
diff --git a/Emby.Server.Implementations/Images/GenreImageProvider.cs b/Emby.Server.Implementations/Images/GenreImageProvider.cs
index 3817882312..6da431c68e 100644
--- a/Emby.Server.Implementations/Images/GenreImageProvider.cs
+++ b/Emby.Server.Implementations/Images/GenreImageProvider.cs
@@ -1,3 +1,5 @@
+#nullable disable
+
 #pragma warning disable CS1591
 
 using System.Collections.Generic;
diff --git a/Emby.Server.Implementations/Images/PlaylistImageProvider.cs b/Emby.Server.Implementations/Images/PlaylistImageProvider.cs
index a4c106e879..b8f0f0d65c 100644
--- a/Emby.Server.Implementations/Images/PlaylistImageProvider.cs
+++ b/Emby.Server.Implementations/Images/PlaylistImageProvider.cs
@@ -1,3 +1,5 @@
+#nullable disable
+
 #pragma warning disable CS1591
 
 using System.Collections.Generic;
diff --git a/Emby.Server.Implementations/Library/ExclusiveLiveStream.cs b/Emby.Server.Implementations/Library/ExclusiveLiveStream.cs
index 236453e805..6c65b58999 100644
--- a/Emby.Server.Implementations/Library/ExclusiveLiveStream.cs
+++ b/Emby.Server.Implementations/Library/ExclusiveLiveStream.cs
@@ -1,3 +1,5 @@
+#nullable disable
+
 #pragma warning disable CS1591
 
 using System;
diff --git a/Emby.Server.Implementations/Library/IgnorePatterns.cs b/Emby.Server.Implementations/Library/IgnorePatterns.cs
index e30a675931..5384c04b3b 100644
--- a/Emby.Server.Implementations/Library/IgnorePatterns.cs
+++ b/Emby.Server.Implementations/Library/IgnorePatterns.cs
@@ -1,5 +1,3 @@
-#nullable enable
-
 using System;
 using System.Linq;
 using DotNet.Globbing;
diff --git a/Emby.Server.Implementations/Library/LibraryManager.cs b/Emby.Server.Implementations/Library/LibraryManager.cs
index 4d207471a2..f8d8197d46 100644
--- a/Emby.Server.Implementations/Library/LibraryManager.cs
+++ b/Emby.Server.Implementations/Library/LibraryManager.cs
@@ -1,3 +1,5 @@
+#nullable disable
+
 #pragma warning disable CS1591
 
 using System;
diff --git a/Emby.Server.Implementations/Library/LiveStreamHelper.cs b/Emby.Server.Implementations/Library/LiveStreamHelper.cs
index c2951dd155..4ef7923db3 100644
--- a/Emby.Server.Implementations/Library/LiveStreamHelper.cs
+++ b/Emby.Server.Implementations/Library/LiveStreamHelper.cs
@@ -1,3 +1,5 @@
+#nullable disable
+
 #pragma warning disable CS1591
 
 using System;
diff --git a/Emby.Server.Implementations/Library/MediaSourceManager.cs b/Emby.Server.Implementations/Library/MediaSourceManager.cs
index 85d6d3043e..38e81d14c4 100644
--- a/Emby.Server.Implementations/Library/MediaSourceManager.cs
+++ b/Emby.Server.Implementations/Library/MediaSourceManager.cs
@@ -1,3 +1,5 @@
+#nullable disable
+
 #pragma warning disable CS1591
 
 using System;
diff --git a/Emby.Server.Implementations/Library/MediaStreamSelector.cs b/Emby.Server.Implementations/Library/MediaStreamSelector.cs
index 28fa062396..b833122ea0 100644
--- a/Emby.Server.Implementations/Library/MediaStreamSelector.cs
+++ b/Emby.Server.Implementations/Library/MediaStreamSelector.cs
@@ -1,3 +1,5 @@
+#nullable disable
+
 #pragma warning disable CS1591
 
 using System;
diff --git a/Emby.Server.Implementations/Library/MusicManager.cs b/Emby.Server.Implementations/Library/MusicManager.cs
index f8bae4fd1a..06300adebc 100644
--- a/Emby.Server.Implementations/Library/MusicManager.cs
+++ b/Emby.Server.Implementations/Library/MusicManager.cs
@@ -1,3 +1,5 @@
+#nullable disable
+
 #pragma warning disable CS1591
 
 using System;
diff --git a/Emby.Server.Implementations/Library/PathExtensions.cs b/Emby.Server.Implementations/Library/PathExtensions.cs
index 0de4edb7e7..86b8039fab 100644
--- a/Emby.Server.Implementations/Library/PathExtensions.cs
+++ b/Emby.Server.Implementations/Library/PathExtensions.cs
@@ -1,5 +1,3 @@
-#nullable enable
-
 using System;
 using System.Diagnostics.CodeAnalysis;
 using MediaBrowser.Common.Providers;
diff --git a/Emby.Server.Implementations/Library/ResolverHelper.cs b/Emby.Server.Implementations/Library/ResolverHelper.cs
index 1d9b448741..ac75e5d3a1 100644
--- a/Emby.Server.Implementations/Library/ResolverHelper.cs
+++ b/Emby.Server.Implementations/Library/ResolverHelper.cs
@@ -1,5 +1,3 @@
-#nullable enable
-
 using System;
 using System.IO;
 using System.Linq;
diff --git a/Emby.Server.Implementations/Library/Resolvers/Audio/AudioResolver.cs b/Emby.Server.Implementations/Library/Resolvers/Audio/AudioResolver.cs
index 4ad84579d8..e893d63350 100644
--- a/Emby.Server.Implementations/Library/Resolvers/Audio/AudioResolver.cs
+++ b/Emby.Server.Implementations/Library/Resolvers/Audio/AudioResolver.cs
@@ -1,3 +1,5 @@
+#nullable disable
+
 #pragma warning disable CS1591
 
 using System;
diff --git a/Emby.Server.Implementations/Library/Resolvers/Audio/MusicAlbumResolver.cs b/Emby.Server.Implementations/Library/Resolvers/Audio/MusicAlbumResolver.cs
index bf32381ebf..8e1eccb10a 100644
--- a/Emby.Server.Implementations/Library/Resolvers/Audio/MusicAlbumResolver.cs
+++ b/Emby.Server.Implementations/Library/Resolvers/Audio/MusicAlbumResolver.cs
@@ -1,3 +1,5 @@
+#nullable disable
+
 using System;
 using System.Collections.Generic;
 using System.Linq;
diff --git a/Emby.Server.Implementations/Library/Resolvers/Audio/MusicArtistResolver.cs b/Emby.Server.Implementations/Library/Resolvers/Audio/MusicArtistResolver.cs
index 60f82806fb..3d2ae95d24 100644
--- a/Emby.Server.Implementations/Library/Resolvers/Audio/MusicArtistResolver.cs
+++ b/Emby.Server.Implementations/Library/Resolvers/Audio/MusicArtistResolver.cs
@@ -1,3 +1,5 @@
+#nullable disable
+
 using System;
 using System.Linq;
 using System.Threading.Tasks;
diff --git a/Emby.Server.Implementations/Library/Resolvers/BaseVideoResolver.cs b/Emby.Server.Implementations/Library/Resolvers/BaseVideoResolver.cs
index 16050185fb..a3dcdc9441 100644
--- a/Emby.Server.Implementations/Library/Resolvers/BaseVideoResolver.cs
+++ b/Emby.Server.Implementations/Library/Resolvers/BaseVideoResolver.cs
@@ -1,3 +1,5 @@
+#nullable disable
+
 #pragma warning disable CS1591
 
 using System;
diff --git a/Emby.Server.Implementations/Library/Resolvers/Books/BookResolver.cs b/Emby.Server.Implementations/Library/Resolvers/Books/BookResolver.cs
index 0525c7e307..68076730b3 100644
--- a/Emby.Server.Implementations/Library/Resolvers/Books/BookResolver.cs
+++ b/Emby.Server.Implementations/Library/Resolvers/Books/BookResolver.cs
@@ -1,3 +1,5 @@
+#nullable disable
+
 #pragma warning disable CS1591
 
 using System;
diff --git a/Emby.Server.Implementations/Library/Resolvers/FolderResolver.cs b/Emby.Server.Implementations/Library/Resolvers/FolderResolver.cs
index 7dbce7a6ef..7aaee017dd 100644
--- a/Emby.Server.Implementations/Library/Resolvers/FolderResolver.cs
+++ b/Emby.Server.Implementations/Library/Resolvers/FolderResolver.cs
@@ -1,3 +1,5 @@
+#nullable disable
+
 using MediaBrowser.Controller.Entities;
 using MediaBrowser.Controller.Library;
 using MediaBrowser.Controller.Resolvers;
diff --git a/Emby.Server.Implementations/Library/Resolvers/ItemResolver.cs b/Emby.Server.Implementations/Library/Resolvers/ItemResolver.cs
index 92fb2a753a..fa45ccf840 100644
--- a/Emby.Server.Implementations/Library/Resolvers/ItemResolver.cs
+++ b/Emby.Server.Implementations/Library/Resolvers/ItemResolver.cs
@@ -1,3 +1,5 @@
+#nullable disable
+
 using MediaBrowser.Controller.Entities;
 using MediaBrowser.Controller.Library;
 using MediaBrowser.Controller.Resolvers;
diff --git a/Emby.Server.Implementations/Library/Resolvers/Movies/BoxSetResolver.cs b/Emby.Server.Implementations/Library/Resolvers/Movies/BoxSetResolver.cs
index 295e9e120b..69d71d0d9a 100644
--- a/Emby.Server.Implementations/Library/Resolvers/Movies/BoxSetResolver.cs
+++ b/Emby.Server.Implementations/Library/Resolvers/Movies/BoxSetResolver.cs
@@ -1,3 +1,5 @@
+#nullable disable
+
 using System;
 using System.IO;
 using MediaBrowser.Controller.Entities;
diff --git a/Emby.Server.Implementations/Library/Resolvers/Movies/MovieResolver.cs b/Emby.Server.Implementations/Library/Resolvers/Movies/MovieResolver.cs
index 16bf4dc4a0..02c5287646 100644
--- a/Emby.Server.Implementations/Library/Resolvers/Movies/MovieResolver.cs
+++ b/Emby.Server.Implementations/Library/Resolvers/Movies/MovieResolver.cs
@@ -1,3 +1,5 @@
+#nullable disable
+
 using System;
 using System.Collections.Generic;
 using System.IO;
diff --git a/Emby.Server.Implementations/Library/Resolvers/PhotoAlbumResolver.cs b/Emby.Server.Implementations/Library/Resolvers/PhotoAlbumResolver.cs
index 204c8a62e7..534bc80ddc 100644
--- a/Emby.Server.Implementations/Library/Resolvers/PhotoAlbumResolver.cs
+++ b/Emby.Server.Implementations/Library/Resolvers/PhotoAlbumResolver.cs
@@ -1,3 +1,5 @@
+#nullable disable
+
 using System;
 using MediaBrowser.Controller.Drawing;
 using MediaBrowser.Controller.Entities;
diff --git a/Emby.Server.Implementations/Library/Resolvers/PhotoResolver.cs b/Emby.Server.Implementations/Library/Resolvers/PhotoResolver.cs
index 3cb6542cf7..57bf40e9ec 100644
--- a/Emby.Server.Implementations/Library/Resolvers/PhotoResolver.cs
+++ b/Emby.Server.Implementations/Library/Resolvers/PhotoResolver.cs
@@ -1,3 +1,5 @@
+#nullable disable
+
 #pragma warning disable CS1591
 
 using System;
diff --git a/Emby.Server.Implementations/Library/Resolvers/PlaylistResolver.cs b/Emby.Server.Implementations/Library/Resolvers/PlaylistResolver.cs
index 5f051321f6..ecd44be477 100644
--- a/Emby.Server.Implementations/Library/Resolvers/PlaylistResolver.cs
+++ b/Emby.Server.Implementations/Library/Resolvers/PlaylistResolver.cs
@@ -1,3 +1,5 @@
+#nullable disable
+
 #pragma warning disable CS1591
 
 using System;
diff --git a/Emby.Server.Implementations/Library/Resolvers/SpecialFolderResolver.cs b/Emby.Server.Implementations/Library/Resolvers/SpecialFolderResolver.cs
index 99f3041909..7b4e143348 100644
--- a/Emby.Server.Implementations/Library/Resolvers/SpecialFolderResolver.cs
+++ b/Emby.Server.Implementations/Library/Resolvers/SpecialFolderResolver.cs
@@ -1,3 +1,5 @@
+#nullable disable
+
 #pragma warning disable CS1591
 
 using System;
diff --git a/Emby.Server.Implementations/Library/Resolvers/TV/EpisodeResolver.cs b/Emby.Server.Implementations/Library/Resolvers/TV/EpisodeResolver.cs
index 6f29bc6494..d6ae910565 100644
--- a/Emby.Server.Implementations/Library/Resolvers/TV/EpisodeResolver.cs
+++ b/Emby.Server.Implementations/Library/Resolvers/TV/EpisodeResolver.cs
@@ -1,3 +1,5 @@
+#nullable disable
+
 using System;
 using System.Linq;
 using MediaBrowser.Controller.Entities;
diff --git a/Emby.Server.Implementations/Library/Resolvers/TV/SeasonResolver.cs b/Emby.Server.Implementations/Library/Resolvers/TV/SeasonResolver.cs
index 768e2e4f5b..7d707df182 100644
--- a/Emby.Server.Implementations/Library/Resolvers/TV/SeasonResolver.cs
+++ b/Emby.Server.Implementations/Library/Resolvers/TV/SeasonResolver.cs
@@ -1,3 +1,5 @@
+#nullable disable
+
 using System.Globalization;
 using Emby.Naming.TV;
 using MediaBrowser.Controller.Entities.TV;
diff --git a/Emby.Server.Implementations/Library/Resolvers/TV/SeriesResolver.cs b/Emby.Server.Implementations/Library/Resolvers/TV/SeriesResolver.cs
index 8fc3e3e75c..a1562abd31 100644
--- a/Emby.Server.Implementations/Library/Resolvers/TV/SeriesResolver.cs
+++ b/Emby.Server.Implementations/Library/Resolvers/TV/SeriesResolver.cs
@@ -1,3 +1,5 @@
+#nullable disable
+
 #pragma warning disable CS1591
 
 using System;
diff --git a/Emby.Server.Implementations/Library/Resolvers/VideoResolver.cs b/Emby.Server.Implementations/Library/Resolvers/VideoResolver.cs
index 62268fce90..9599faea4b 100644
--- a/Emby.Server.Implementations/Library/Resolvers/VideoResolver.cs
+++ b/Emby.Server.Implementations/Library/Resolvers/VideoResolver.cs
@@ -1,3 +1,5 @@
+#nullable disable
+
 #pragma warning disable CS1591
 
 using MediaBrowser.Controller.Entities;
diff --git a/Emby.Server.Implementations/Library/SearchEngine.cs b/Emby.Server.Implementations/Library/SearchEngine.cs
index bcdf854ca3..26e615fa08 100644
--- a/Emby.Server.Implementations/Library/SearchEngine.cs
+++ b/Emby.Server.Implementations/Library/SearchEngine.cs
@@ -1,3 +1,5 @@
+#nullable disable
+
 #pragma warning disable CS1591
 
 using System;
diff --git a/Emby.Server.Implementations/Library/UserDataManager.cs b/Emby.Server.Implementations/Library/UserDataManager.cs
index 827e3c64b3..667e466133 100644
--- a/Emby.Server.Implementations/Library/UserDataManager.cs
+++ b/Emby.Server.Implementations/Library/UserDataManager.cs
@@ -1,3 +1,5 @@
+#nullable disable
+
 #pragma warning disable CS1591
 
 using System;
diff --git a/Emby.Server.Implementations/Library/UserViewManager.cs b/Emby.Server.Implementations/Library/UserViewManager.cs
index ac041bcf6c..e2da672a3c 100644
--- a/Emby.Server.Implementations/Library/UserViewManager.cs
+++ b/Emby.Server.Implementations/Library/UserViewManager.cs
@@ -1,3 +1,5 @@
+#nullable disable
+
 #pragma warning disable CS1591
 
 using System;
diff --git a/Emby.Server.Implementations/LiveTv/EmbyTV/DirectRecorder.cs b/Emby.Server.Implementations/LiveTv/EmbyTV/DirectRecorder.cs
index 7a6b1d8b61..3fcadf5b1b 100644
--- a/Emby.Server.Implementations/LiveTv/EmbyTV/DirectRecorder.cs
+++ b/Emby.Server.Implementations/LiveTv/EmbyTV/DirectRecorder.cs
@@ -1,3 +1,5 @@
+#nullable disable
+
 #pragma warning disable CS1591
 
 using System;
diff --git a/Emby.Server.Implementations/LiveTv/EmbyTV/EmbyTV.cs b/Emby.Server.Implementations/LiveTv/EmbyTV/EmbyTV.cs
index 28a2095e16..7970631201 100644
--- a/Emby.Server.Implementations/LiveTv/EmbyTV/EmbyTV.cs
+++ b/Emby.Server.Implementations/LiveTv/EmbyTV/EmbyTV.cs
@@ -1,3 +1,5 @@
+#nullable disable
+
 #pragma warning disable CS1591
 
 using System;
diff --git a/Emby.Server.Implementations/LiveTv/EmbyTV/EncodedRecorder.cs b/Emby.Server.Implementations/LiveTv/EmbyTV/EncodedRecorder.cs
index 9372b0f6c3..26e4ef1ed9 100644
--- a/Emby.Server.Implementations/LiveTv/EmbyTV/EncodedRecorder.cs
+++ b/Emby.Server.Implementations/LiveTv/EmbyTV/EncodedRecorder.cs
@@ -1,3 +1,5 @@
+#nullable disable
+
 #pragma warning disable CS1591
 
 using System;
diff --git a/Emby.Server.Implementations/LiveTv/EmbyTV/EpgChannelData.cs b/Emby.Server.Implementations/LiveTv/EmbyTV/EpgChannelData.cs
index 8c27ca76e3..0ec52a9598 100644
--- a/Emby.Server.Implementations/LiveTv/EmbyTV/EpgChannelData.cs
+++ b/Emby.Server.Implementations/LiveTv/EmbyTV/EpgChannelData.cs
@@ -6,7 +6,6 @@ using MediaBrowser.Controller.LiveTv;
 
 namespace Emby.Server.Implementations.LiveTv.EmbyTV
 {
-
     internal class EpgChannelData
     {
 
@@ -39,13 +38,13 @@ namespace Emby.Server.Implementations.LiveTv.EmbyTV
             }
         }
 
-        public ChannelInfo GetChannelById(string id)
+        public ChannelInfo? GetChannelById(string id)
             => _channelsById.GetValueOrDefault(id);
 
-        public ChannelInfo GetChannelByNumber(string number)
+        public ChannelInfo? GetChannelByNumber(string number)
             => _channelsByNumber.GetValueOrDefault(number);
 
-        public ChannelInfo GetChannelByName(string name)
+        public ChannelInfo? GetChannelByName(string name)
             => _channelsByName.GetValueOrDefault(name);
 
         public static string NormalizeName(string value)
diff --git a/Emby.Server.Implementations/LiveTv/EmbyTV/ItemDataProvider.cs b/Emby.Server.Implementations/LiveTv/EmbyTV/ItemDataProvider.cs
index 1cac9cb963..bdab8c3e4b 100644
--- a/Emby.Server.Implementations/LiveTv/EmbyTV/ItemDataProvider.cs
+++ b/Emby.Server.Implementations/LiveTv/EmbyTV/ItemDataProvider.cs
@@ -1,3 +1,5 @@
+#nullable disable
+
 #pragma warning disable CS1591
 
 using System;
diff --git a/Emby.Server.Implementations/LiveTv/EmbyTV/RecordingHelper.cs b/Emby.Server.Implementations/LiveTv/EmbyTV/RecordingHelper.cs
index 32245f899e..1088638691 100644
--- a/Emby.Server.Implementations/LiveTv/EmbyTV/RecordingHelper.cs
+++ b/Emby.Server.Implementations/LiveTv/EmbyTV/RecordingHelper.cs
@@ -1,3 +1,5 @@
+#nullable disable
+
 #pragma warning disable CS1591
 
 using System;
diff --git a/Emby.Server.Implementations/LiveTv/EmbyTV/TimerManager.cs b/Emby.Server.Implementations/LiveTv/EmbyTV/TimerManager.cs
index 1efa90e256..6c52a9a73d 100644
--- a/Emby.Server.Implementations/LiveTv/EmbyTV/TimerManager.cs
+++ b/Emby.Server.Implementations/LiveTv/EmbyTV/TimerManager.cs
@@ -1,3 +1,5 @@
+#nullable disable
+
 #pragma warning disable CS1591
 
 using System;
diff --git a/Emby.Server.Implementations/LiveTv/Listings/SchedulesDirect.cs b/Emby.Server.Implementations/LiveTv/Listings/SchedulesDirect.cs
index 9af65cabba..00d02873c5 100644
--- a/Emby.Server.Implementations/LiveTv/Listings/SchedulesDirect.cs
+++ b/Emby.Server.Implementations/LiveTv/Listings/SchedulesDirect.cs
@@ -1,3 +1,5 @@
+#nullable disable
+
 #pragma warning disable CS1591
 
 using System;
diff --git a/Emby.Server.Implementations/LiveTv/Listings/XmlTvListingsProvider.cs b/Emby.Server.Implementations/LiveTv/Listings/XmlTvListingsProvider.cs
index 6824aa4423..ebad4eddf1 100644
--- a/Emby.Server.Implementations/LiveTv/Listings/XmlTvListingsProvider.cs
+++ b/Emby.Server.Implementations/LiveTv/Listings/XmlTvListingsProvider.cs
@@ -1,3 +1,5 @@
+#nullable disable
+
 #pragma warning disable CS1591
 
 using System;
diff --git a/Emby.Server.Implementations/LiveTv/LiveTvDtoService.cs b/Emby.Server.Implementations/LiveTv/LiveTvDtoService.cs
index 6af49dd45e..21e1409ac0 100644
--- a/Emby.Server.Implementations/LiveTv/LiveTvDtoService.cs
+++ b/Emby.Server.Implementations/LiveTv/LiveTvDtoService.cs
@@ -1,3 +1,5 @@
+#nullable disable
+
 #pragma warning disable CS1591
 
 using System;
diff --git a/Emby.Server.Implementations/LiveTv/LiveTvManager.cs b/Emby.Server.Implementations/LiveTv/LiveTvManager.cs
index 1145d8aa1e..1f16289002 100644
--- a/Emby.Server.Implementations/LiveTv/LiveTvManager.cs
+++ b/Emby.Server.Implementations/LiveTv/LiveTvManager.cs
@@ -1,3 +1,5 @@
+#nullable disable
+
 #pragma warning disable CS1591
 
 using System;
diff --git a/Emby.Server.Implementations/LiveTv/LiveTvMediaSourceProvider.cs b/Emby.Server.Implementations/LiveTv/LiveTvMediaSourceProvider.cs
index 3a738fd5d2..ecd28097d3 100644
--- a/Emby.Server.Implementations/LiveTv/LiveTvMediaSourceProvider.cs
+++ b/Emby.Server.Implementations/LiveTv/LiveTvMediaSourceProvider.cs
@@ -1,3 +1,5 @@
+#nullable disable
+
 #pragma warning disable CS1591
 
 using System;
diff --git a/Emby.Server.Implementations/LiveTv/TunerHosts/BaseTunerHost.cs b/Emby.Server.Implementations/LiveTv/TunerHosts/BaseTunerHost.cs
index fbcd4ef372..00a37bb022 100644
--- a/Emby.Server.Implementations/LiveTv/TunerHosts/BaseTunerHost.cs
+++ b/Emby.Server.Implementations/LiveTv/TunerHosts/BaseTunerHost.cs
@@ -1,3 +1,5 @@
+#nullable disable
+
 #pragma warning disable CS1591
 
 using System;
diff --git a/Emby.Server.Implementations/LiveTv/TunerHosts/HdHomerun/Channels.cs b/Emby.Server.Implementations/LiveTv/TunerHosts/HdHomerun/Channels.cs
index 740cbb66ee..0f04531896 100644
--- a/Emby.Server.Implementations/LiveTv/TunerHosts/HdHomerun/Channels.cs
+++ b/Emby.Server.Implementations/LiveTv/TunerHosts/HdHomerun/Channels.cs
@@ -1,3 +1,5 @@
+#nullable disable
+
 namespace Emby.Server.Implementations.LiveTv.TunerHosts.HdHomerun
 {
     internal class Channels
diff --git a/Emby.Server.Implementations/LiveTv/TunerHosts/HdHomerun/DiscoverResponse.cs b/Emby.Server.Implementations/LiveTv/TunerHosts/HdHomerun/DiscoverResponse.cs
index 09d77f8382..42068cd340 100644
--- a/Emby.Server.Implementations/LiveTv/TunerHosts/HdHomerun/DiscoverResponse.cs
+++ b/Emby.Server.Implementations/LiveTv/TunerHosts/HdHomerun/DiscoverResponse.cs
@@ -1,3 +1,5 @@
+#nullable disable
+
 using System;
 
 namespace Emby.Server.Implementations.LiveTv.TunerHosts.HdHomerun
diff --git a/Emby.Server.Implementations/LiveTv/TunerHosts/HdHomerun/HdHomerunHost.cs b/Emby.Server.Implementations/LiveTv/TunerHosts/HdHomerun/HdHomerunHost.cs
index bbac6e0551..c5700db715 100644
--- a/Emby.Server.Implementations/LiveTv/TunerHosts/HdHomerun/HdHomerunHost.cs
+++ b/Emby.Server.Implementations/LiveTv/TunerHosts/HdHomerun/HdHomerunHost.cs
@@ -1,3 +1,5 @@
+#nullable disable
+
 #pragma warning disable CS1591
 
 using System;
diff --git a/Emby.Server.Implementations/LiveTv/TunerHosts/HdHomerun/HdHomerunManager.cs b/Emby.Server.Implementations/LiveTv/TunerHosts/HdHomerun/HdHomerunManager.cs
index a7fda1d72e..3016eeda24 100644
--- a/Emby.Server.Implementations/LiveTv/TunerHosts/HdHomerun/HdHomerunManager.cs
+++ b/Emby.Server.Implementations/LiveTv/TunerHosts/HdHomerun/HdHomerunManager.cs
@@ -1,3 +1,5 @@
+#nullable disable
+
 #pragma warning disable CS1591
 
 using System;
diff --git a/Emby.Server.Implementations/LiveTv/TunerHosts/HdHomerun/HdHomerunUdpStream.cs b/Emby.Server.Implementations/LiveTv/TunerHosts/HdHomerun/HdHomerunUdpStream.cs
index b16ccc561a..50a2d9abb3 100644
--- a/Emby.Server.Implementations/LiveTv/TunerHosts/HdHomerun/HdHomerunUdpStream.cs
+++ b/Emby.Server.Implementations/LiveTv/TunerHosts/HdHomerun/HdHomerunUdpStream.cs
@@ -1,3 +1,5 @@
+#nullable disable
+
 #pragma warning disable CS1591
 
 using System;
diff --git a/Emby.Server.Implementations/LiveTv/TunerHosts/LiveStream.cs b/Emby.Server.Implementations/LiveTv/TunerHosts/LiveStream.cs
index f8baf55da7..96a678c1d3 100644
--- a/Emby.Server.Implementations/LiveTv/TunerHosts/LiveStream.cs
+++ b/Emby.Server.Implementations/LiveTv/TunerHosts/LiveStream.cs
@@ -1,3 +1,5 @@
+#nullable disable
+
 #pragma warning disable CS1591
 
 using System;
diff --git a/Emby.Server.Implementations/LiveTv/TunerHosts/M3UTunerHost.cs b/Emby.Server.Implementations/LiveTv/TunerHosts/M3UTunerHost.cs
index 4b170b2e4e..69035dac96 100644
--- a/Emby.Server.Implementations/LiveTv/TunerHosts/M3UTunerHost.cs
+++ b/Emby.Server.Implementations/LiveTv/TunerHosts/M3UTunerHost.cs
@@ -1,3 +1,5 @@
+#nullable disable
+
 #pragma warning disable CS1591
 
 using System;
diff --git a/Emby.Server.Implementations/LiveTv/TunerHosts/M3uParser.cs b/Emby.Server.Implementations/LiveTv/TunerHosts/M3uParser.cs
index 84d4161499..48a0c3cd37 100644
--- a/Emby.Server.Implementations/LiveTv/TunerHosts/M3uParser.cs
+++ b/Emby.Server.Implementations/LiveTv/TunerHosts/M3uParser.cs
@@ -1,3 +1,5 @@
+#nullable disable
+
 #pragma warning disable CS1591
 
 using System;
diff --git a/Emby.Server.Implementations/LiveTv/TunerHosts/SharedHttpStream.cs b/Emby.Server.Implementations/LiveTv/TunerHosts/SharedHttpStream.cs
index eeb2426f4f..137ed27e20 100644
--- a/Emby.Server.Implementations/LiveTv/TunerHosts/SharedHttpStream.cs
+++ b/Emby.Server.Implementations/LiveTv/TunerHosts/SharedHttpStream.cs
@@ -1,3 +1,5 @@
+#nullable disable
+
 #pragma warning disable CS1591
 
 using System;
diff --git a/Emby.Server.Implementations/Localization/LocalizationManager.cs b/Emby.Server.Implementations/Localization/LocalizationManager.cs
index 220e423bf5..dd5dee1d16 100644
--- a/Emby.Server.Implementations/Localization/LocalizationManager.cs
+++ b/Emby.Server.Implementations/Localization/LocalizationManager.cs
@@ -1,3 +1,5 @@
+#nullable disable
+
 using System;
 using System.Collections.Concurrent;
 using System.Collections.Generic;
diff --git a/Emby.Server.Implementations/MediaEncoder/EncodingManager.cs b/Emby.Server.Implementations/MediaEncoder/EncodingManager.cs
index 031b5d2e72..8aaa1f7bbe 100644
--- a/Emby.Server.Implementations/MediaEncoder/EncodingManager.cs
+++ b/Emby.Server.Implementations/MediaEncoder/EncodingManager.cs
@@ -1,3 +1,5 @@
+#nullable disable
+
 #pragma warning disable CS1591
 
 using System;
diff --git a/Emby.Server.Implementations/Net/SocketFactory.cs b/Emby.Server.Implementations/Net/SocketFactory.cs
index 0781a0e333..1377286168 100644
--- a/Emby.Server.Implementations/Net/SocketFactory.cs
+++ b/Emby.Server.Implementations/Net/SocketFactory.cs
@@ -1,3 +1,5 @@
+#nullable disable
+
 #pragma warning disable CS1591
 
 using System;
diff --git a/Emby.Server.Implementations/Net/UdpSocket.cs b/Emby.Server.Implementations/Net/UdpSocket.cs
index 4e25768cf6..a8b18d2925 100644
--- a/Emby.Server.Implementations/Net/UdpSocket.cs
+++ b/Emby.Server.Implementations/Net/UdpSocket.cs
@@ -1,3 +1,5 @@
+#nullable disable
+
 #pragma warning disable CS1591
 
 using System;
diff --git a/Emby.Server.Implementations/Playlists/PlaylistManager.cs b/Emby.Server.Implementations/Playlists/PlaylistManager.cs
index 2d1a559f16..9a1ca99467 100644
--- a/Emby.Server.Implementations/Playlists/PlaylistManager.cs
+++ b/Emby.Server.Implementations/Playlists/PlaylistManager.cs
@@ -1,3 +1,5 @@
+#nullable disable
+
 #pragma warning disable CS1591
 
 using System;
diff --git a/Emby.Server.Implementations/Plugins/PluginManager.cs b/Emby.Server.Implementations/Plugins/PluginManager.cs
index 14df20936c..48281b75f6 100644
--- a/Emby.Server.Implementations/Plugins/PluginManager.cs
+++ b/Emby.Server.Implementations/Plugins/PluginManager.cs
@@ -1,5 +1,3 @@
-#nullable enable
-
 using System;
 using System.Collections.Generic;
 using System.Globalization;
diff --git a/Emby.Server.Implementations/QuickConnect/QuickConnectManager.cs b/Emby.Server.Implementations/QuickConnect/QuickConnectManager.cs
index 0259dc436b..7cfd1fced9 100644
--- a/Emby.Server.Implementations/QuickConnect/QuickConnectManager.cs
+++ b/Emby.Server.Implementations/QuickConnect/QuickConnectManager.cs
@@ -1,3 +1,5 @@
+#nullable disable
+
 using System;
 using System.Collections.Concurrent;
 using System.Globalization;
diff --git a/Emby.Server.Implementations/ScheduledTasks/ScheduledTaskWorker.cs b/Emby.Server.Implementations/ScheduledTasks/ScheduledTaskWorker.cs
index 101d9b5377..ccbd4289ea 100644
--- a/Emby.Server.Implementations/ScheduledTasks/ScheduledTaskWorker.cs
+++ b/Emby.Server.Implementations/ScheduledTasks/ScheduledTaskWorker.cs
@@ -1,3 +1,5 @@
+#nullable disable
+
 #pragma warning disable CS1591
 
 using System;
diff --git a/Emby.Server.Implementations/ScheduledTasks/TaskManager.cs b/Emby.Server.Implementations/ScheduledTasks/TaskManager.cs
index af316e1083..4f0df75bf8 100644
--- a/Emby.Server.Implementations/ScheduledTasks/TaskManager.cs
+++ b/Emby.Server.Implementations/ScheduledTasks/TaskManager.cs
@@ -1,3 +1,5 @@
+#nullable disable
+
 #pragma warning disable CS1591
 
 using System;
diff --git a/Emby.Server.Implementations/ScheduledTasks/Tasks/ChapterImagesTask.cs b/Emby.Server.Implementations/ScheduledTasks/Tasks/ChapterImagesTask.cs
index 2312c85d97..baeb86a221 100644
--- a/Emby.Server.Implementations/ScheduledTasks/Tasks/ChapterImagesTask.cs
+++ b/Emby.Server.Implementations/ScheduledTasks/Tasks/ChapterImagesTask.cs
@@ -140,8 +140,10 @@ namespace Emby.Server.Implementations.ScheduledTasks
                         previouslyFailedImages.Add(key);
 
                         var parentPath = Path.GetDirectoryName(failHistoryPath);
-
-                        Directory.CreateDirectory(parentPath);
+                        if (parentPath != null)
+                        {
+                            Directory.CreateDirectory(parentPath);
+                        }
 
                         string text = string.Join('|', previouslyFailedImages);
                         File.WriteAllText(failHistoryPath, text);
diff --git a/Emby.Server.Implementations/ScheduledTasks/Tasks/CleanActivityLogTask.cs b/Emby.Server.Implementations/ScheduledTasks/Tasks/CleanActivityLogTask.cs
index 4abbf784b2..50ba9bc899 100644
--- a/Emby.Server.Implementations/ScheduledTasks/Tasks/CleanActivityLogTask.cs
+++ b/Emby.Server.Implementations/ScheduledTasks/Tasks/CleanActivityLogTask.cs
@@ -1,4 +1,4 @@
-using System;
+using System;
 using System.Collections.Generic;
 using System.Linq;
 using System.Threading;
@@ -75,4 +75,4 @@ namespace Emby.Server.Implementations.ScheduledTasks.Tasks
             return Enumerable.Empty<TaskTriggerInfo>();
         }
     }
-}
\ No newline at end of file
+}
diff --git a/Emby.Server.Implementations/ScheduledTasks/Triggers/DailyTrigger.cs b/Emby.Server.Implementations/ScheduledTasks/Triggers/DailyTrigger.cs
index 3b40320ab8..3b63536a42 100644
--- a/Emby.Server.Implementations/ScheduledTasks/Triggers/DailyTrigger.cs
+++ b/Emby.Server.Implementations/ScheduledTasks/Triggers/DailyTrigger.cs
@@ -1,3 +1,5 @@
+#nullable disable
+
 using System;
 using System.Threading;
 using MediaBrowser.Model.Tasks;
diff --git a/Emby.Server.Implementations/ScheduledTasks/Triggers/IntervalTrigger.cs b/Emby.Server.Implementations/ScheduledTasks/Triggers/IntervalTrigger.cs
index b04fd7c7e2..e13782fe02 100644
--- a/Emby.Server.Implementations/ScheduledTasks/Triggers/IntervalTrigger.cs
+++ b/Emby.Server.Implementations/ScheduledTasks/Triggers/IntervalTrigger.cs
@@ -1,3 +1,5 @@
+#nullable disable
+
 using System;
 using System.Linq;
 using System.Threading;
diff --git a/Emby.Server.Implementations/ScheduledTasks/Triggers/StartupTrigger.cs b/Emby.Server.Implementations/ScheduledTasks/Triggers/StartupTrigger.cs
index 7cd5493da8..ced14195bb 100644
--- a/Emby.Server.Implementations/ScheduledTasks/Triggers/StartupTrigger.cs
+++ b/Emby.Server.Implementations/ScheduledTasks/Triggers/StartupTrigger.cs
@@ -1,3 +1,5 @@
+#nullable disable
+
 #pragma warning disable CS1591
 
 using System;
diff --git a/Emby.Server.Implementations/ScheduledTasks/Triggers/WeeklyTrigger.cs b/Emby.Server.Implementations/ScheduledTasks/Triggers/WeeklyTrigger.cs
index 0c0ebec082..a67f940b75 100644
--- a/Emby.Server.Implementations/ScheduledTasks/Triggers/WeeklyTrigger.cs
+++ b/Emby.Server.Implementations/ScheduledTasks/Triggers/WeeklyTrigger.cs
@@ -1,3 +1,5 @@
+#nullable disable
+
 using System;
 using System.Threading;
 using MediaBrowser.Model.Tasks;
diff --git a/Emby.Server.Implementations/Security/AuthenticationRepository.cs b/Emby.Server.Implementations/Security/AuthenticationRepository.cs
index 76f863c951..30823ab8f5 100644
--- a/Emby.Server.Implementations/Security/AuthenticationRepository.cs
+++ b/Emby.Server.Implementations/Security/AuthenticationRepository.cs
@@ -1,3 +1,5 @@
+#nullable disable
+
 #pragma warning disable CS1591
 
 using System;
diff --git a/Emby.Server.Implementations/Serialization/MyXmlSerializer.cs b/Emby.Server.Implementations/Serialization/MyXmlSerializer.cs
index 27024e4e1c..8d8b82f0a4 100644
--- a/Emby.Server.Implementations/Serialization/MyXmlSerializer.cs
+++ b/Emby.Server.Implementations/Serialization/MyXmlSerializer.cs
@@ -19,7 +19,9 @@ namespace Emby.Server.Implementations.Serialization
             new ConcurrentDictionary<string, XmlSerializer>();
 
         private static XmlSerializer GetSerializer(Type type)
-            => _serializers.GetOrAdd(type.FullName, _ => new XmlSerializer(type));
+            => _serializers.GetOrAdd(
+                type.FullName ?? throw new ArgumentException($"Invalid type {type}."),
+                _ => new XmlSerializer(type));
 
         /// <summary>
         /// Serializes to writer.
@@ -38,7 +40,7 @@ namespace Emby.Server.Implementations.Serialization
         /// <param name="type">The type.</param>
         /// <param name="stream">The stream.</param>
         /// <returns>System.Object.</returns>
-        public object DeserializeFromStream(Type type, Stream stream)
+        public object? DeserializeFromStream(Type type, Stream stream)
         {
             using (var reader = XmlReader.Create(stream))
             {
@@ -81,7 +83,7 @@ namespace Emby.Server.Implementations.Serialization
         /// <param name="type">The type.</param>
         /// <param name="file">The file.</param>
         /// <returns>System.Object.</returns>
-        public object DeserializeFromFile(Type type, string file)
+        public object? DeserializeFromFile(Type type, string file)
         {
             using (var stream = File.OpenRead(file))
             {
@@ -95,7 +97,7 @@ namespace Emby.Server.Implementations.Serialization
         /// <param name="type">The type.</param>
         /// <param name="buffer">The buffer.</param>
         /// <returns>System.Object.</returns>
-        public object DeserializeFromBytes(Type type, byte[] buffer)
+        public object? DeserializeFromBytes(Type type, byte[] buffer)
         {
             using (var stream = new MemoryStream(buffer, 0, buffer.Length, false, true))
             {
diff --git a/Emby.Server.Implementations/Session/SessionManager.cs b/Emby.Server.Implementations/Session/SessionManager.cs
index 6844152ea5..ef467da7ed 100644
--- a/Emby.Server.Implementations/Session/SessionManager.cs
+++ b/Emby.Server.Implementations/Session/SessionManager.cs
@@ -1,3 +1,5 @@
+#nullable disable
+
 #pragma warning disable CS1591
 
 using System;
diff --git a/Emby.Server.Implementations/Session/SessionWebSocketListener.cs b/Emby.Server.Implementations/Session/SessionWebSocketListener.cs
index 39c369a01d..e9e3ca7f4b 100644
--- a/Emby.Server.Implementations/Session/SessionWebSocketListener.cs
+++ b/Emby.Server.Implementations/Session/SessionWebSocketListener.cs
@@ -1,3 +1,5 @@
+#nullable disable
+
 using System;
 using System.Collections.Generic;
 using System.Linq;
diff --git a/Emby.Server.Implementations/Session/WebSocketController.cs b/Emby.Server.Implementations/Session/WebSocketController.cs
index a653b58c2b..ed1dfca592 100644
--- a/Emby.Server.Implementations/Session/WebSocketController.cs
+++ b/Emby.Server.Implementations/Session/WebSocketController.cs
@@ -1,6 +1,5 @@
 #pragma warning disable CS1591
 #pragma warning disable SA1600
-#nullable enable
 
 using System;
 using System.Collections.Generic;
diff --git a/Emby.Server.Implementations/Sorting/AiredEpisodeOrderComparer.cs b/Emby.Server.Implementations/Sorting/AiredEpisodeOrderComparer.cs
index 60698e803d..2b0ab536f9 100644
--- a/Emby.Server.Implementations/Sorting/AiredEpisodeOrderComparer.cs
+++ b/Emby.Server.Implementations/Sorting/AiredEpisodeOrderComparer.cs
@@ -16,7 +16,7 @@ namespace Emby.Server.Implementations.Sorting
         /// <param name="x">The x.</param>
         /// <param name="y">The y.</param>
         /// <returns>System.Int32.</returns>
-        public int Compare(BaseItem x, BaseItem y)
+        public int Compare(BaseItem? x, BaseItem? y)
         {
             if (x == null)
             {
diff --git a/Emby.Server.Implementations/Sorting/AlbumArtistComparer.cs b/Emby.Server.Implementations/Sorting/AlbumArtistComparer.cs
index 7657cc74e1..42e644970c 100644
--- a/Emby.Server.Implementations/Sorting/AlbumArtistComparer.cs
+++ b/Emby.Server.Implementations/Sorting/AlbumArtistComparer.cs
@@ -18,7 +18,7 @@ namespace Emby.Server.Implementations.Sorting
         /// <param name="x">The x.</param>
         /// <param name="y">The y.</param>
         /// <returns>System.Int32.</returns>
-        public int Compare(BaseItem x, BaseItem y)
+        public int Compare(BaseItem? x, BaseItem? y)
         {
             return string.Compare(GetValue(x), GetValue(y), StringComparison.CurrentCultureIgnoreCase);
         }
@@ -28,7 +28,7 @@ namespace Emby.Server.Implementations.Sorting
         /// </summary>
         /// <param name="x">The x.</param>
         /// <returns>System.String.</returns>
-        private static string GetValue(BaseItem x)
+        private static string? GetValue(BaseItem? x)
         {
             var audio = x as IHasAlbumArtist;
 
diff --git a/Emby.Server.Implementations/Sorting/AlbumComparer.cs b/Emby.Server.Implementations/Sorting/AlbumComparer.cs
index 7dfdd9ecff..1db3f5e9ca 100644
--- a/Emby.Server.Implementations/Sorting/AlbumComparer.cs
+++ b/Emby.Server.Implementations/Sorting/AlbumComparer.cs
@@ -17,7 +17,7 @@ namespace Emby.Server.Implementations.Sorting
         /// <param name="x">The x.</param>
         /// <param name="y">The y.</param>
         /// <returns>System.Int32.</returns>
-        public int Compare(BaseItem x, BaseItem y)
+        public int Compare(BaseItem? x, BaseItem? y)
         {
             return string.Compare(GetValue(x), GetValue(y), StringComparison.CurrentCultureIgnoreCase);
         }
@@ -27,7 +27,7 @@ namespace Emby.Server.Implementations.Sorting
         /// </summary>
         /// <param name="x">The x.</param>
         /// <returns>System.String.</returns>
-        private static string GetValue(BaseItem x)
+        private static string? GetValue(BaseItem? x)
         {
             var audio = x as Audio;
 
diff --git a/Emby.Server.Implementations/Sorting/ArtistComparer.cs b/Emby.Server.Implementations/Sorting/ArtistComparer.cs
index 756d3c5b6c..98bee3fd9f 100644
--- a/Emby.Server.Implementations/Sorting/ArtistComparer.cs
+++ b/Emby.Server.Implementations/Sorting/ArtistComparer.cs
@@ -15,7 +15,7 @@ namespace Emby.Server.Implementations.Sorting
         public string Name => ItemSortBy.Artist;
 
         /// <inheritdoc />
-        public int Compare(BaseItem x, BaseItem y)
+        public int Compare(BaseItem? x, BaseItem? y)
         {
             return string.Compare(GetValue(x), GetValue(y), StringComparison.CurrentCultureIgnoreCase);
         }
@@ -25,7 +25,7 @@ namespace Emby.Server.Implementations.Sorting
         /// </summary>
         /// <param name="x">The x.</param>
         /// <returns>System.String.</returns>
-        private static string GetValue(BaseItem x)
+        private static string? GetValue(BaseItem? x)
         {
             if (!(x is Audio audio))
             {
diff --git a/Emby.Server.Implementations/Sorting/CommunityRatingComparer.cs b/Emby.Server.Implementations/Sorting/CommunityRatingComparer.cs
index 980954ba03..5f142fa4bb 100644
--- a/Emby.Server.Implementations/Sorting/CommunityRatingComparer.cs
+++ b/Emby.Server.Implementations/Sorting/CommunityRatingComparer.cs
@@ -21,7 +21,7 @@ namespace Emby.Server.Implementations.Sorting
         /// <param name="x">The x.</param>
         /// <param name="y">The y.</param>
         /// <returns>System.Int32.</returns>
-        public int Compare(BaseItem x, BaseItem y)
+        public int Compare(BaseItem? x, BaseItem? y)
         {
             if (x == null)
             {
diff --git a/Emby.Server.Implementations/Sorting/CriticRatingComparer.cs b/Emby.Server.Implementations/Sorting/CriticRatingComparer.cs
index fa136c36d0..d20dedc2d4 100644
--- a/Emby.Server.Implementations/Sorting/CriticRatingComparer.cs
+++ b/Emby.Server.Implementations/Sorting/CriticRatingComparer.cs
@@ -15,14 +15,14 @@ namespace Emby.Server.Implementations.Sorting
         /// <param name="x">The x.</param>
         /// <param name="y">The y.</param>
         /// <returns>System.Int32.</returns>
-        public int Compare(BaseItem x, BaseItem y)
+        public int Compare(BaseItem? x, BaseItem? y)
         {
             return GetValue(x).CompareTo(GetValue(y));
         }
 
-        private static float GetValue(BaseItem x)
+        private static float GetValue(BaseItem? x)
         {
-            return x.CriticRating ?? 0;
+            return x?.CriticRating ?? 0;
         }
 
         /// <summary>
diff --git a/Emby.Server.Implementations/Sorting/DateCreatedComparer.cs b/Emby.Server.Implementations/Sorting/DateCreatedComparer.cs
index cbca300d2f..d3f10f78cb 100644
--- a/Emby.Server.Implementations/Sorting/DateCreatedComparer.cs
+++ b/Emby.Server.Implementations/Sorting/DateCreatedComparer.cs
@@ -16,7 +16,7 @@ namespace Emby.Server.Implementations.Sorting
         /// <param name="x">The x.</param>
         /// <param name="y">The y.</param>
         /// <returns>System.Int32.</returns>
-        public int Compare(BaseItem x, BaseItem y)
+        public int Compare(BaseItem? x, BaseItem? y)
         {
             if (x == null)
             {
diff --git a/Emby.Server.Implementations/Sorting/DateLastMediaAddedComparer.cs b/Emby.Server.Implementations/Sorting/DateLastMediaAddedComparer.cs
index 03ff19d21c..b1cb123ce1 100644
--- a/Emby.Server.Implementations/Sorting/DateLastMediaAddedComparer.cs
+++ b/Emby.Server.Implementations/Sorting/DateLastMediaAddedComparer.cs
@@ -1,3 +1,4 @@
+#nullable disable
 #pragma warning disable CS1591
 
 using System;
diff --git a/Emby.Server.Implementations/Sorting/DatePlayedComparer.cs b/Emby.Server.Implementations/Sorting/DatePlayedComparer.cs
index 16bd2aff86..08a44319f2 100644
--- a/Emby.Server.Implementations/Sorting/DatePlayedComparer.cs
+++ b/Emby.Server.Implementations/Sorting/DatePlayedComparer.cs
@@ -1,3 +1,5 @@
+#nullable disable
+
 using System;
 using Jellyfin.Data.Entities;
 using MediaBrowser.Controller.Entities;
diff --git a/Emby.Server.Implementations/Sorting/IsFavoriteOrLikeComparer.cs b/Emby.Server.Implementations/Sorting/IsFavoriteOrLikeComparer.cs
index 0c4e82d011..73e628cf75 100644
--- a/Emby.Server.Implementations/Sorting/IsFavoriteOrLikeComparer.cs
+++ b/Emby.Server.Implementations/Sorting/IsFavoriteOrLikeComparer.cs
@@ -1,3 +1,4 @@
+#nullable disable
 #pragma warning disable CS1591
 
 using Jellyfin.Data.Entities;
diff --git a/Emby.Server.Implementations/Sorting/IsFolderComparer.cs b/Emby.Server.Implementations/Sorting/IsFolderComparer.cs
index a35192eff8..3c5ddeefaa 100644
--- a/Emby.Server.Implementations/Sorting/IsFolderComparer.cs
+++ b/Emby.Server.Implementations/Sorting/IsFolderComparer.cs
@@ -20,7 +20,7 @@ namespace Emby.Server.Implementations.Sorting
         /// <param name="x">The x.</param>
         /// <param name="y">The y.</param>
         /// <returns>System.Int32.</returns>
-        public int Compare(BaseItem x, BaseItem y)
+        public int Compare(BaseItem? x, BaseItem? y)
         {
             return GetValue(x).CompareTo(GetValue(y));
         }
@@ -30,9 +30,9 @@ namespace Emby.Server.Implementations.Sorting
         /// </summary>
         /// <param name="x">The x.</param>
         /// <returns>System.String.</returns>
-        private static int GetValue(BaseItem x)
+        private static int GetValue(BaseItem? x)
         {
-            return x.IsFolder ? 0 : 1;
+            return x?.IsFolder ?? true ? 0 : 1;
         }
     }
 }
diff --git a/Emby.Server.Implementations/Sorting/IsPlayedComparer.cs b/Emby.Server.Implementations/Sorting/IsPlayedComparer.cs
index d95948406f..7d77a8bc5a 100644
--- a/Emby.Server.Implementations/Sorting/IsPlayedComparer.cs
+++ b/Emby.Server.Implementations/Sorting/IsPlayedComparer.cs
@@ -1,3 +1,5 @@
+#nullable disable
+
 #pragma warning disable CS1591
 
 using Jellyfin.Data.Entities;
diff --git a/Emby.Server.Implementations/Sorting/IsUnplayedComparer.cs b/Emby.Server.Implementations/Sorting/IsUnplayedComparer.cs
index 1632c5a7a9..926835f906 100644
--- a/Emby.Server.Implementations/Sorting/IsUnplayedComparer.cs
+++ b/Emby.Server.Implementations/Sorting/IsUnplayedComparer.cs
@@ -1,3 +1,5 @@
+#nullable disable
+
 #pragma warning disable CS1591
 
 using Jellyfin.Data.Entities;
diff --git a/Emby.Server.Implementations/Sorting/NameComparer.cs b/Emby.Server.Implementations/Sorting/NameComparer.cs
index da020d8d8e..4de81a69e3 100644
--- a/Emby.Server.Implementations/Sorting/NameComparer.cs
+++ b/Emby.Server.Implementations/Sorting/NameComparer.cs
@@ -16,7 +16,7 @@ namespace Emby.Server.Implementations.Sorting
         /// <param name="x">The x.</param>
         /// <param name="y">The y.</param>
         /// <returns>System.Int32.</returns>
-        public int Compare(BaseItem x, BaseItem y)
+        public int Compare(BaseItem? x, BaseItem? y)
         {
             if (x == null)
             {
diff --git a/Emby.Server.Implementations/Sorting/OfficialRatingComparer.cs b/Emby.Server.Implementations/Sorting/OfficialRatingComparer.cs
index 76bb798b5f..a81f78ebfc 100644
--- a/Emby.Server.Implementations/Sorting/OfficialRatingComparer.cs
+++ b/Emby.Server.Implementations/Sorting/OfficialRatingComparer.cs
@@ -29,7 +29,7 @@ namespace Emby.Server.Implementations.Sorting
         /// <param name="x">The x.</param>
         /// <param name="y">The y.</param>
         /// <returns>System.Int32.</returns>
-        public int Compare(BaseItem x, BaseItem y)
+        public int Compare(BaseItem? x, BaseItem? y)
         {
             if (x == null)
             {
diff --git a/Emby.Server.Implementations/Sorting/PlayCountComparer.cs b/Emby.Server.Implementations/Sorting/PlayCountComparer.cs
index 5c28303229..04e4865cbf 100644
--- a/Emby.Server.Implementations/Sorting/PlayCountComparer.cs
+++ b/Emby.Server.Implementations/Sorting/PlayCountComparer.cs
@@ -1,3 +1,5 @@
+#nullable disable
+
 using Jellyfin.Data.Entities;
 using MediaBrowser.Controller.Entities;
 using MediaBrowser.Controller.Library;
diff --git a/Emby.Server.Implementations/Sorting/PremiereDateComparer.cs b/Emby.Server.Implementations/Sorting/PremiereDateComparer.cs
index 92ac04dc66..c98f97bf1e 100644
--- a/Emby.Server.Implementations/Sorting/PremiereDateComparer.cs
+++ b/Emby.Server.Implementations/Sorting/PremiereDateComparer.cs
@@ -16,7 +16,7 @@ namespace Emby.Server.Implementations.Sorting
         /// <param name="x">The x.</param>
         /// <param name="y">The y.</param>
         /// <returns>System.Int32.</returns>
-        public int Compare(BaseItem x, BaseItem y)
+        public int Compare(BaseItem? x, BaseItem? y)
         {
             return GetDate(x).CompareTo(GetDate(y));
         }
@@ -26,8 +26,13 @@ namespace Emby.Server.Implementations.Sorting
         /// </summary>
         /// <param name="x">The x.</param>
         /// <returns>DateTime.</returns>
-        private static DateTime GetDate(BaseItem x)
+        private static DateTime GetDate(BaseItem? x)
         {
+            if (x == null)
+            {
+                return DateTime.MinValue;
+            }
+
             if (x.PremiereDate.HasValue)
             {
                 return x.PremiereDate.Value;
diff --git a/Emby.Server.Implementations/Sorting/ProductionYearComparer.cs b/Emby.Server.Implementations/Sorting/ProductionYearComparer.cs
index e2857df0b9..df9f9957d6 100644
--- a/Emby.Server.Implementations/Sorting/ProductionYearComparer.cs
+++ b/Emby.Server.Implementations/Sorting/ProductionYearComparer.cs
@@ -15,7 +15,7 @@ namespace Emby.Server.Implementations.Sorting
         /// <param name="x">The x.</param>
         /// <param name="y">The y.</param>
         /// <returns>System.Int32.</returns>
-        public int Compare(BaseItem x, BaseItem y)
+        public int Compare(BaseItem? x, BaseItem? y)
         {
             return GetValue(x).CompareTo(GetValue(y));
         }
@@ -25,8 +25,13 @@ namespace Emby.Server.Implementations.Sorting
         /// </summary>
         /// <param name="x">The x.</param>
         /// <returns>DateTime.</returns>
-        private static int GetValue(BaseItem x)
+        private static int GetValue(BaseItem? x)
         {
+            if (x == null)
+            {
+                return 0;
+            }
+
             if (x.ProductionYear.HasValue)
             {
                 return x.ProductionYear.Value;
diff --git a/Emby.Server.Implementations/Sorting/RandomComparer.cs b/Emby.Server.Implementations/Sorting/RandomComparer.cs
index 7739d04182..af3bc27508 100644
--- a/Emby.Server.Implementations/Sorting/RandomComparer.cs
+++ b/Emby.Server.Implementations/Sorting/RandomComparer.cs
@@ -16,7 +16,7 @@ namespace Emby.Server.Implementations.Sorting
         /// <param name="x">The x.</param>
         /// <param name="y">The y.</param>
         /// <returns>System.Int32.</returns>
-        public int Compare(BaseItem x, BaseItem y)
+        public int Compare(BaseItem? x, BaseItem? y)
         {
             return Guid.NewGuid().CompareTo(Guid.NewGuid());
         }
diff --git a/Emby.Server.Implementations/Sorting/RuntimeComparer.cs b/Emby.Server.Implementations/Sorting/RuntimeComparer.cs
index dde44333d5..1293153031 100644
--- a/Emby.Server.Implementations/Sorting/RuntimeComparer.cs
+++ b/Emby.Server.Implementations/Sorting/RuntimeComparer.cs
@@ -1,3 +1,5 @@
+#nullable disable
+
 using System;
 using MediaBrowser.Controller.Entities;
 using MediaBrowser.Controller.Sorting;
diff --git a/Emby.Server.Implementations/Sorting/SeriesSortNameComparer.cs b/Emby.Server.Implementations/Sorting/SeriesSortNameComparer.cs
index b9205ee076..4123a59f8b 100644
--- a/Emby.Server.Implementations/Sorting/SeriesSortNameComparer.cs
+++ b/Emby.Server.Implementations/Sorting/SeriesSortNameComparer.cs
@@ -1,3 +1,5 @@
+#nullable disable
+
 #pragma warning disable CS1591
 
 using System;
diff --git a/Emby.Server.Implementations/Sorting/SortNameComparer.cs b/Emby.Server.Implementations/Sorting/SortNameComparer.cs
index f745e193b4..8d30716d39 100644
--- a/Emby.Server.Implementations/Sorting/SortNameComparer.cs
+++ b/Emby.Server.Implementations/Sorting/SortNameComparer.cs
@@ -1,3 +1,5 @@
+#nullable disable
+
 using System;
 using MediaBrowser.Controller.Entities;
 using MediaBrowser.Controller.Sorting;
diff --git a/Emby.Server.Implementations/Sorting/StartDateComparer.cs b/Emby.Server.Implementations/Sorting/StartDateComparer.cs
index 558a3d3513..c3df7c47e6 100644
--- a/Emby.Server.Implementations/Sorting/StartDateComparer.cs
+++ b/Emby.Server.Implementations/Sorting/StartDateComparer.cs
@@ -1,3 +1,5 @@
+#nullable disable
+
 #pragma warning disable CS1591
 
 using System;
diff --git a/Emby.Server.Implementations/Sorting/StudioComparer.cs b/Emby.Server.Implementations/Sorting/StudioComparer.cs
index 5766dc542b..01445c5254 100644
--- a/Emby.Server.Implementations/Sorting/StudioComparer.cs
+++ b/Emby.Server.Implementations/Sorting/StudioComparer.cs
@@ -1,3 +1,5 @@
+#nullable disable
+
 #pragma warning disable CS1591
 
 using System;
diff --git a/Emby.Server.Implementations/SyncPlay/Group.cs b/Emby.Server.Implementations/SyncPlay/Group.cs
index 7c2ad2477a..12efff261b 100644
--- a/Emby.Server.Implementations/SyncPlay/Group.cs
+++ b/Emby.Server.Implementations/SyncPlay/Group.cs
@@ -1,3 +1,5 @@
+#nullable disable
+
 using System;
 using System.Collections.Generic;
 using System.Linq;
diff --git a/Emby.Server.Implementations/SyncPlay/SyncPlayManager.cs b/Emby.Server.Implementations/SyncPlay/SyncPlayManager.cs
index 72c0a838e2..993456196d 100644
--- a/Emby.Server.Implementations/SyncPlay/SyncPlayManager.cs
+++ b/Emby.Server.Implementations/SyncPlay/SyncPlayManager.cs
@@ -1,3 +1,5 @@
+#nullable disable
+
 using System;
 using System.Collections.Concurrent;
 using System.Collections.Generic;
diff --git a/Emby.Server.Implementations/TV/TVSeriesManager.cs b/Emby.Server.Implementations/TV/TVSeriesManager.cs
index 829df64bfb..a837f09cac 100644
--- a/Emby.Server.Implementations/TV/TVSeriesManager.cs
+++ b/Emby.Server.Implementations/TV/TVSeriesManager.cs
@@ -1,3 +1,5 @@
+#nullable disable
+
 #pragma warning disable CS1591
 
 using System;
diff --git a/Emby.Server.Implementations/Udp/UdpServer.cs b/Emby.Server.Implementations/Udp/UdpServer.cs
index db5265e79d..750f001680 100644
--- a/Emby.Server.Implementations/Udp/UdpServer.cs
+++ b/Emby.Server.Implementations/Udp/UdpServer.cs
@@ -1,3 +1,5 @@
+#nullable disable
+
 using System;
 using System.Net;
 using System.Net.Sockets;
diff --git a/Emby.Server.Implementations/Updates/InstallationManager.cs b/Emby.Server.Implementations/Updates/InstallationManager.cs
index 653b1381b9..2351b7d8c6 100644
--- a/Emby.Server.Implementations/Updates/InstallationManager.cs
+++ b/Emby.Server.Implementations/Updates/InstallationManager.cs
@@ -1,3 +1,5 @@
+#nullable disable
+
 #nullable enable
 
 using System;
diff --git a/Jellyfin.Api/Controllers/DynamicHlsController.cs b/Jellyfin.Api/Controllers/DynamicHlsController.cs
index 9f3216de34..555062e556 100644
--- a/Jellyfin.Api/Controllers/DynamicHlsController.cs
+++ b/Jellyfin.Api/Controllers/DynamicHlsController.cs
@@ -1760,9 +1760,9 @@ namespace Jellyfin.Api.Controllers
 
         private static FileSystemMetadata? GetLastTranscodingFile(string playlist, string segmentExtension, IFileSystem fileSystem)
         {
-            var folder = Path.GetDirectoryName(playlist);
+            var folder = Path.GetDirectoryName(playlist) ?? throw new ArgumentException("Path can't be a root directory.", nameof(playlist));
 
-            var filePrefix = Path.GetFileNameWithoutExtension(playlist) ?? string.Empty;
+            var filePrefix = Path.GetFileNameWithoutExtension(playlist);
 
             try
             {
diff --git a/Jellyfin.Api/Helpers/TranscodingJobHelper.cs b/Jellyfin.Api/Helpers/TranscodingJobHelper.cs
index 5770c13d7e..b4db0c83e9 100644
--- a/Jellyfin.Api/Helpers/TranscodingJobHelper.cs
+++ b/Jellyfin.Api/Helpers/TranscodingJobHelper.cs
@@ -379,7 +379,9 @@ namespace Jellyfin.Api.Helpers
         /// <param name="outputFilePath">The output file path.</param>
         private void DeleteHlsPartialStreamFiles(string outputFilePath)
         {
-            var directory = Path.GetDirectoryName(outputFilePath);
+            var directory = Path.GetDirectoryName(outputFilePath)
+                ?? throw new ArgumentException("Path can't be a root directory.", nameof(outputFilePath));
+
             var name = Path.GetFileNameWithoutExtension(outputFilePath);
 
             var filesToDelete = _fileSystem.GetFilePaths(directory)
diff --git a/Jellyfin.Api/Models/PlaybackDtos/TranscodingThrottler.cs b/Jellyfin.Api/Models/PlaybackDtos/TranscodingThrottler.cs
index e33e552edb..7b32d76ba7 100644
--- a/Jellyfin.Api/Models/PlaybackDtos/TranscodingThrottler.cs
+++ b/Jellyfin.Api/Models/PlaybackDtos/TranscodingThrottler.cs
@@ -145,7 +145,8 @@ namespace Jellyfin.Api.Models.PlaybackDtos
             var transcodingPositionTicks = job.TranscodingPositionTicks ?? 0;
             var downloadPositionTicks = job.DownloadPositionTicks ?? 0;
 
-            var path = job.Path;
+            var path = job.Path ?? throw new ArgumentException("Path can't be null.");
+
             var gapLengthInTicks = TimeSpan.FromSeconds(thresholdSeconds).Ticks;
 
             if (downloadPositionTicks > 0 && transcodingPositionTicks > 0)
diff --git a/Jellyfin.Server/Migrations/Routines/MigrateUserDb.cs b/Jellyfin.Server/Migrations/Routines/MigrateUserDb.cs
index a15a381772..96bd2ccc40 100644
--- a/Jellyfin.Server/Migrations/Routines/MigrateUserDb.cs
+++ b/Jellyfin.Server/Migrations/Routines/MigrateUserDb.cs
@@ -82,11 +82,14 @@ namespace Jellyfin.Server.Migrations.Routines
 
                     var userDataDir = Path.Combine(_paths.UserConfigurationDirectoryPath, mockup.Name);
 
-                    var config = File.Exists(Path.Combine(userDataDir, "config.xml"))
-                        ? (UserConfiguration)_xmlSerializer.DeserializeFromFile(typeof(UserConfiguration), Path.Combine(userDataDir, "config.xml"))
+                    var configPath = Path.Combine(userDataDir, "config.xml");
+                    var config = File.Exists(configPath)
+                        ? (UserConfiguration?)_xmlSerializer.DeserializeFromFile(typeof(UserConfiguration), configPath) ?? new UserConfiguration()
                         : new UserConfiguration();
-                    var policy = File.Exists(Path.Combine(userDataDir, "policy.xml"))
-                        ? (UserPolicy)_xmlSerializer.DeserializeFromFile(typeof(UserPolicy), Path.Combine(userDataDir, "policy.xml"))
+
+                    var policyPath = Path.Combine(userDataDir, "policy.xml");
+                    var policy = File.Exists(policyPath)
+                        ? (UserPolicy?)_xmlSerializer.DeserializeFromFile(typeof(UserPolicy), policyPath) ?? new UserPolicy()
                         : new UserPolicy();
                     policy.AuthenticationProviderId = policy.AuthenticationProviderId?.Replace(
                         "Emby.Server.Implementations.Library",
diff --git a/MediaBrowser.Controller/Extensions/StringExtensions.cs b/MediaBrowser.Controller/Extensions/StringExtensions.cs
index 48bd9522a8..1853896eec 100644
--- a/MediaBrowser.Controller/Extensions/StringExtensions.cs
+++ b/MediaBrowser.Controller/Extensions/StringExtensions.cs
@@ -1,6 +1,7 @@
 #pragma warning disable CS1591
 
 using System;
+using System.Collections.Generic;
 using System.Globalization;
 using System.Linq;
 using System.Text;
diff --git a/MediaBrowser.Controller/Net/ISessionContext.cs b/MediaBrowser.Controller/Net/ISessionContext.cs
index a60dc2ea19..6b896b41f4 100644
--- a/MediaBrowser.Controller/Net/ISessionContext.cs
+++ b/MediaBrowser.Controller/Net/ISessionContext.cs
@@ -10,10 +10,10 @@ namespace MediaBrowser.Controller.Net
     {
         SessionInfo GetSession(object requestContext);
 
-        User GetUser(object requestContext);
+        User? GetUser(object requestContext);
 
         SessionInfo GetSession(HttpContext requestContext);
 
-        User GetUser(HttpContext requestContext);
+        User? GetUser(HttpContext requestContext);
     }
 }
diff --git a/MediaBrowser.Controller/Sorting/IBaseItemComparer.cs b/MediaBrowser.Controller/Sorting/IBaseItemComparer.cs
index 727cbe639c..07fe1ea8a9 100644
--- a/MediaBrowser.Controller/Sorting/IBaseItemComparer.cs
+++ b/MediaBrowser.Controller/Sorting/IBaseItemComparer.cs
@@ -6,7 +6,7 @@ namespace MediaBrowser.Controller.Sorting
     /// <summary>
     /// Interface IBaseItemComparer.
     /// </summary>
-    public interface IBaseItemComparer : IComparer<BaseItem>
+    public interface IBaseItemComparer : IComparer<BaseItem?>
     {
         /// <summary>
         /// Gets the name.
diff --git a/MediaBrowser.Model/IO/IFileSystem.cs b/MediaBrowser.Model/IO/IFileSystem.cs
index e5c26430a8..be4f1e16b5 100644
--- a/MediaBrowser.Model/IO/IFileSystem.cs
+++ b/MediaBrowser.Model/IO/IFileSystem.cs
@@ -1,4 +1,3 @@
-#nullable disable
 #pragma warning disable CS1591
 
 using System;
@@ -25,7 +24,7 @@ namespace MediaBrowser.Model.IO
         /// </summary>
         /// <param name="filename">The filename.</param>
         /// <returns>System.String.</returns>
-        string ResolveShortcut(string filename);
+        string? ResolveShortcut(string filename);
 
         /// <summary>
         /// Creates the shortcut.
@@ -160,7 +159,7 @@ namespace MediaBrowser.Model.IO
         /// <returns>All found files.</returns>
         IEnumerable<FileSystemMetadata> GetFiles(string path, bool recursive = false);
 
-        IEnumerable<FileSystemMetadata> GetFiles(string path, IReadOnlyList<string> extensions, bool enableCaseSensitiveExtensions, bool recursive);
+        IEnumerable<FileSystemMetadata> GetFiles(string path, IReadOnlyList<string>? extensions, bool enableCaseSensitiveExtensions, bool recursive);
 
         /// <summary>
         /// Gets the file system entries.
@@ -186,7 +185,7 @@ namespace MediaBrowser.Model.IO
         /// <returns>IEnumerable&lt;System.String&gt;.</returns>
         IEnumerable<string> GetFilePaths(string path, bool recursive = false);
 
-        IEnumerable<string> GetFilePaths(string path, string[] extensions, bool enableCaseSensitiveExtensions, bool recursive);
+        IEnumerable<string> GetFilePaths(string path, string[]? extensions, bool enableCaseSensitiveExtensions, bool recursive);
 
         /// <summary>
         /// Gets the file system entry paths.
diff --git a/MediaBrowser.Model/IO/IShortcutHandler.cs b/MediaBrowser.Model/IO/IShortcutHandler.cs
index 14d5c4b62f..2c364a962f 100644
--- a/MediaBrowser.Model/IO/IShortcutHandler.cs
+++ b/MediaBrowser.Model/IO/IShortcutHandler.cs
@@ -15,7 +15,7 @@ namespace MediaBrowser.Model.IO
         /// </summary>
         /// <param name="shortcutPath">The shortcut path.</param>
         /// <returns>System.String.</returns>
-        string Resolve(string shortcutPath);
+        string? Resolve(string shortcutPath);
 
         /// <summary>
         /// Creates the specified shortcut path.
diff --git a/MediaBrowser.Model/IO/IStreamHelper.cs b/MediaBrowser.Model/IO/IStreamHelper.cs
index 0e09db16e8..f900da5567 100644
--- a/MediaBrowser.Model/IO/IStreamHelper.cs
+++ b/MediaBrowser.Model/IO/IStreamHelper.cs
@@ -9,7 +9,7 @@ namespace MediaBrowser.Model.IO
 {
     public interface IStreamHelper
     {
-        Task CopyToAsync(Stream source, Stream destination, int bufferSize, Action onStarted, CancellationToken cancellationToken);
+        Task CopyToAsync(Stream source, Stream destination, int bufferSize, Action? onStarted, CancellationToken cancellationToken);
 
         Task CopyToAsync(Stream source, Stream destination, int bufferSize, int emptyReadLimit, CancellationToken cancellationToken);
 
diff --git a/MediaBrowser.Model/Tasks/ITaskTrigger.cs b/MediaBrowser.Model/Tasks/ITaskTrigger.cs
index cbd60cca18..db9fba6964 100644
--- a/MediaBrowser.Model/Tasks/ITaskTrigger.cs
+++ b/MediaBrowser.Model/Tasks/ITaskTrigger.cs
@@ -11,7 +11,7 @@ namespace MediaBrowser.Model.Tasks
         /// <summary>
         /// Fires when the trigger condition is satisfied and the task should run.
         /// </summary>
-        event EventHandler<EventArgs> Triggered;
+        event EventHandler<EventArgs>? Triggered;
 
         /// <summary>
         /// Gets or sets the options of this task.