Fixed: Don't try to create metadata images if source files doesn't exist

Closes #6015

src/NzbDrone.Core/Extras/Metadata/MetadataService.cs

@@ -1,4 +1,4 @@
-using System;
+using System;
 using System.Collections.Generic;
 using System.IO;
 using System.Linq;
@@ -443,6 +443,7 @@ namespace NzbDrone.Core.Extras.Metadata
         private void DownloadImage(Series series, ImageFileResult image)
         {
             var fullPath = Path.Combine(series.Path, image.RelativePath);
+            var downloaded = true;
 
             try
             {
@@ -450,12 +451,19 @@ namespace NzbDrone.Core.Extras.Metadata
                 {
                     _httpClient.DownloadFile(image.Url, fullPath);
                 }
-                else
+                else if (_diskProvider.FileExists(image.Url))
                 {
                     _diskProvider.CopyFile(image.Url, fullPath);
                 }
+                else
+                {
+                    downloaded = false;
+                }
 
-                _mediaFileAttributeService.SetFilePermissions(fullPath);
+                if (downloaded)
+                {
+                    _mediaFileAttributeService.SetFilePermissions(fullPath);
+                }
             }
             catch (HttpException ex)
             {