diff --git a/src/NzbDrone.Common.Test/PathExtensionFixture.cs b/src/NzbDrone.Common.Test/PathExtensionFixture.cs
index db140d626..11f8c21f3 100644
--- a/src/NzbDrone.Common.Test/PathExtensionFixture.cs
+++ b/src/NzbDrone.Common.Test/PathExtensionFixture.cs
@@ -138,20 +138,34 @@ namespace NzbDrone.Common.Test
         }
 
         [TestCase(@"C:\Test\mydir", @"C:\Test")]
-        [TestCase(@"C:\Test\", @"C:")]
+        [TestCase(@"C:\Test\", @"C:\")]
         [TestCase(@"C:\", null)]
+        [TestCase(@"\\server\share", null)]
+        [TestCase(@"\\server\share\test", @"\\server\share")]
+        public void path_should_return_parent_windows(string path, string parentPath)
+        {
+            WindowsOnly();
+            path.GetParentPath().Should().Be(parentPath);
+        }
+
         [TestCase(@"/", null)]
         [TestCase(@"/test", null)]
-        public void path_should_return_parent(string path, string parentPath)
+        public void path_should_return_parent_mono(string path, string parentPath)
         {
+            MonoOnly();
             path.GetParentPath().Should().Be(parentPath);
         }
 
         [Test]
         public void path_should_return_parent_for_oversized_path()
         {
-            var path       = @"/media/2e168617-f2ae-43fb-b88c-3663af1c8eea/downloads/sabnzbd/nzbdrone/Some.Real.Big.Thing/With.Alot.Of.Nested.Directories/Some.Real.Big.Thing/With.Alot.Of.Nested.Directories/Some.Real.Big.Thing/With.Alot.Of.Nested.Directories/Some.Real.Big.Thing/With.Alot.Of.Nested.Directories/Some.Real.Big.Thing/With.Alot.Of.Nested.Directories";
-            var parentPath = @"/media/2e168617-f2ae-43fb-b88c-3663af1c8eea/downloads/sabnzbd/nzbdrone/Some.Real.Big.Thing/With.Alot.Of.Nested.Directories/Some.Real.Big.Thing/With.Alot.Of.Nested.Directories/Some.Real.Big.Thing/With.Alot.Of.Nested.Directories/Some.Real.Big.Thing/With.Alot.Of.Nested.Directories/Some.Real.Big.Thing";
+            MonoOnly();
+
+            // This test will fail on Windows if long path support is not enabled: https://www.howtogeek.com/266621/how-to-make-windows-10-accept-file-paths-over-260-characters/
+            // It will also fail if the app isn't configured to use long path (such as resharper): https://blogs.msdn.microsoft.com/jeremykuhne/2016/07/30/net-4-6-2-and-long-paths-on-windows-10/
+
+            var path       = @"C:\media\2e168617-f2ae-43fb-b88c-3663af1c8eea\downloads\sabnzbd\nzbdrone\Some.Real.Big.Thing\With.Alot.Of.Nested.Directories\Some.Real.Big.Thing\With.Alot.Of.Nested.Directories\Some.Real.Big.Thing\With.Alot.Of.Nested.Directories\Some.Real.Big.Thing\With.Alot.Of.Nested.Directories\Some.Real.Big.Thing\With.Alot.Of.Nested.Directories";
+            var parentPath = @"C:\media\2e168617-f2ae-43fb-b88c-3663af1c8eea\downloads\sabnzbd\nzbdrone\Some.Real.Big.Thing\With.Alot.Of.Nested.Directories\Some.Real.Big.Thing\With.Alot.Of.Nested.Directories\Some.Real.Big.Thing\With.Alot.Of.Nested.Directories\Some.Real.Big.Thing\With.Alot.Of.Nested.Directories\Some.Real.Big.Thing";
 
             path.GetParentPath().Should().Be(parentPath);
         }
diff --git a/src/NzbDrone.Common/Extensions/PathExtensions.cs b/src/NzbDrone.Common/Extensions/PathExtensions.cs
index ff95d8973..10aa28b74 100644
--- a/src/NzbDrone.Common/Extensions/PathExtensions.cs
+++ b/src/NzbDrone.Common/Extensions/PathExtensions.cs
@@ -24,6 +24,8 @@ namespace NzbDrone.Common.Extensions
         private static readonly string UPDATE_CLIENT_FOLDER_NAME = "Sonarr.Update" + Path.DirectorySeparatorChar;
         private static readonly string UPDATE_LOG_FOLDER_NAME = "UpdateLogs" + Path.DirectorySeparatorChar;
 
+        private static readonly Regex PARENT_PATH_END_SLASH_REGEX = new Regex(@"(?<!:)\\$", RegexOptions.Compiled);
+
         public static string CleanFilePath(this string path)
         {
             Ensure.That(path, () => path).IsNotNullOrWhiteSpace();
@@ -67,16 +69,11 @@ namespace NzbDrone.Common.Extensions
 
         public static string GetParentPath(this string childPath)
         {
-            var parentPath = childPath.TrimEnd('\\', '/');
+            var cleanPath = OsInfo.IsWindows
+                ? PARENT_PATH_END_SLASH_REGEX.Replace(childPath, "")
+                : childPath.TrimEnd(Path.DirectorySeparatorChar);
 
-            var index = parentPath.LastIndexOfAny(new[] { '\\', '/' });
-
-            if (index > 0)
-            {
-                return parentPath.Substring(0, index);
-            }
-
-            return null;
+            return Directory.GetParent(cleanPath)?.FullName;
         }
 
         public static bool IsParentPath(this string parentPath, string childPath)
diff --git a/src/NzbDrone.Core.Test/MediaFiles/ImportApprovedEpisodesFixture.cs b/src/NzbDrone.Core.Test/MediaFiles/ImportApprovedEpisodesFixture.cs
index f16be5c30..d6755949a 100644
--- a/src/NzbDrone.Core.Test/MediaFiles/ImportApprovedEpisodesFixture.cs
+++ b/src/NzbDrone.Core.Test/MediaFiles/ImportApprovedEpisodesFixture.cs
@@ -346,7 +346,7 @@ namespace NzbDrone.Core.Test.MediaFiles
         public void should_get_relative_path_when_there_is_no_grandparent()
         {
             var name = "Series.Title.S01E01.720p.HDTV.x264-Sonarr";
-            var outputPath = Path.Combine(@"C:\".AsOsAgnostic());
+            var outputPath = @"C:\".AsOsAgnostic();
             var localEpisode = _approvedDecisions.First().LocalEpisode;
 
             localEpisode.FolderEpisodeInfo = new ParsedEpisodeInfo { ReleaseTitle = name };
@@ -357,6 +357,23 @@ namespace NzbDrone.Core.Test.MediaFiles
             Mocker.GetMock<IMediaFileService>().Verify(v => v.Add(It.Is<EpisodeFile>(c => c.OriginalFilePath == $"{name}.mkv".AsOsAgnostic())));
         }
 
+        [Test]
+        public void should_get_relative_path_when_there_is_no_grandparent_for_UNC_path()
+        {
+            WindowsOnly();
+
+            var name = "Series.Title.S01E01.720p.HDTV.x264-Sonarr";
+            var outputPath = @"\\server\share";
+            var localEpisode = _approvedDecisions.First().LocalEpisode;
+
+            localEpisode.FolderEpisodeInfo = new ParsedEpisodeInfo { ReleaseTitle = name };
+            localEpisode.Path = Path.Combine(outputPath, name + ".mkv");
+
+            Subject.Import(new List<ImportDecision> { _approvedDecisions.First() }, true, null);
+
+            Mocker.GetMock<IMediaFileService>().Verify(v => v.Add(It.Is<EpisodeFile>(c => c.OriginalFilePath == $"{name}.mkv")));
+        }
+
         [Test]
         public void should_delete_existing_metadata_files_with_the_same_path()
         {