diff --git a/src/NzbDrone.Common/Http/HttpUri.cs b/src/NzbDrone.Common/Http/HttpUri.cs
index 23e47be94..e630e6e14 100644
--- a/src/NzbDrone.Common/Http/HttpUri.cs
+++ b/src/NzbDrone.Common/Http/HttpUri.cs
@@ -8,7 +8,7 @@ namespace NzbDrone.Common.Http
 {
     public class HttpUri : IEquatable<HttpUri>
     {
-        private static readonly Regex RegexUri = new Regex(@"^(?:(?<scheme>[a-z]+):)?(?://(?<host>[-A-Z0-9.]+)(?::(?<port>[0-9]{1,5}))?)?(?<path>(?:(?:(?<=^)|/)[^/?#\r\n]+)+/?|/)?(?:\?(?<query>[^#\r\n]*))?(?:\#(?<fragment>.*))?$", RegexOptions.Compiled | RegexOptions.IgnoreCase);
+        private static readonly Regex RegexUri = new Regex(@"^(?:(?<scheme>[a-z]+):)?(?://(?<host>[-_A-Z0-9.]+)(?::(?<port>[0-9]{1,5}))?)?(?<path>(?:(?:(?<=^)|/)[^/?#\r\n]+)+/?|/)?(?:\?(?<query>[^#\r\n]*))?(?:\#(?<fragment>.*))?$", RegexOptions.Compiled | RegexOptions.IgnoreCase);
 
         private readonly string _uri;
         public string FullUri => _uri;