This should fix the bug where a folder was tried to be retagged with the same error.

NzbDrone.6.0.ReSharper

@@ -9,6 +9,13 @@
     </CSS>
     <CSharp>
       <FormatSettings>
+        <ALIGN_FIRST_ARG_BY_PAREN>True</ALIGN_FIRST_ARG_BY_PAREN>
+        <ALIGN_MULTILINE_FOR_STMT>False</ALIGN_MULTILINE_FOR_STMT>
+        <CONTINUOUS_INDENT_MULTIPLIER>2</CONTINUOUS_INDENT_MULTIPLIER>
+        <FORCE_ATTRIBUTE_STYLE>SEPARATE</FORCE_ATTRIBUTE_STYLE>
+        <INDENT_NESTED_FIXED_STMT>True</INDENT_NESTED_FIXED_STMT>
+        <INDENT_NESTED_USINGS_STMT>True</INDENT_NESTED_USINGS_STMT>
+        <LINE_FEED_AT_FILE_END>True</LINE_FEED_AT_FILE_END>
         <MODIFIERS_ORDER IsNull="False">
           <Item>public</Item>
           <Item>protected</Item>
@@ -25,8 +32,30 @@
           <Item>unsafe</Item>
           <Item>volatile</Item>
         </MODIFIERS_ORDER>
+        <SPACE_AFTER_TYPECAST_PARENTHESES>False</SPACE_AFTER_TYPECAST_PARENTHESES>
+        <SPACE_AROUND_ARROW_OP>True</SPACE_AROUND_ARROW_OP>
+        <SPACE_AROUND_MULTIPLICATIVE_OP>True</SPACE_AROUND_MULTIPLICATIVE_OP>
+        <SPACE_BEFORE_CATCH_PARENTHESES>False</SPACE_BEFORE_CATCH_PARENTHESES>
+        <SPACE_BEFORE_FIXED_PARENTHESES>False</SPACE_BEFORE_FIXED_PARENTHESES>
+        <SPACE_BEFORE_FOR_PARENTHESES>False</SPACE_BEFORE_FOR_PARENTHESES>
+        <SPACE_BEFORE_FOR_SEMICOLON>True</SPACE_BEFORE_FOR_SEMICOLON>
+        <SPACE_BEFORE_FOREACH_PARENTHESES>False</SPACE_BEFORE_FOREACH_PARENTHESES>
+        <SPACE_BEFORE_IF_PARENTHESES>False</SPACE_BEFORE_IF_PARENTHESES>
+        <SPACE_BEFORE_LOCK_PARENTHESES>False</SPACE_BEFORE_LOCK_PARENTHESES>
+        <SPACE_BEFORE_SIZEOF_PARENTHESES>False</SPACE_BEFORE_SIZEOF_PARENTHESES>
+        <SPACE_BEFORE_SWITCH_PARENTHESES>False</SPACE_BEFORE_SWITCH_PARENTHESES>
+        <SPACE_BEFORE_TYPE_PARAMETER_ANGLE>True</SPACE_BEFORE_TYPE_PARAMETER_ANGLE>
+        <SPACE_BEFORE_TYPE_PARAMETER_CONSTRAINT_COLON>False</SPACE_BEFORE_TYPE_PARAMETER_CONSTRAINT_COLON>
+        <SPACE_BEFORE_TYPEOF_PARENTHESES>False</SPACE_BEFORE_TYPEOF_PARENTHESES>
+        <SPACE_BEFORE_USING_PARENTHESES>False</SPACE_BEFORE_USING_PARENTHESES>
+        <SPACE_BEFORE_WHILE_PARENTHESES>False</SPACE_BEFORE_WHILE_PARENTHESES>
+        <STICK_COMMENT>False</STICK_COMMENT>
       </FormatSettings>
-      <UsingsSettings />
+      <UsingsSettings>
+        <MandatoryImports IsNull="False">
+          <Item>System.Linq</Item>
+        </MandatoryImports>
+      </UsingsSettings>
       <Naming2>
         <EventHandlerPatternLong>$object$_On$event$</EventHandlerPatternLong>
         <EventHandlerPatternShort>$event$Handler</EventHandlerPatternShort>
@@ -79,8 +108,8 @@
       <PredefinedRule Inspect="True" Prefix="_" Suffix="" Style="aaBb" ElementKind="PublicFields" />
       <PredefinedRule Inspect="True" Prefix="_" Suffix="" Style="aaBb" ElementKind="PrivateInstanceFields" />
       <PredefinedRule Inspect="True" Prefix="_" Suffix="" Style="aaBb" ElementKind="PrivateStaticFields" />
-      <PredefinedRule Inspect="True" Prefix="" Suffix="" Style="AaBb" ElementKind="Constants" />
+      <PredefinedRule Inspect="True" Prefix="" Suffix="" Style="AA_BB" ElementKind="Constants" />
-      <PredefinedRule Inspect="True" Prefix="" Suffix="" Style="AaBb" ElementKind="PrivateConstants" />
+      <PredefinedRule Inspect="True" Prefix="" Suffix="" Style="AA_BB" ElementKind="PrivateConstants" />
       <PredefinedRule Inspect="True" Prefix="" Suffix="" Style="AaBb" ElementKind="StaticReadonly" />
       <PredefinedRule Inspect="True" Prefix="" Suffix="" Style="AaBb" ElementKind="EnumMember" />
       <PredefinedRule Inspect="True" Prefix="" Suffix="" Style="AaBb" ElementKind="Other" />

NzbDrone.Core.Test/ProviderTests/PostDownloadProviderTests/PostDownloadProviderFixture.cs

@@ -19,7 +19,7 @@ namespace NzbDrone.Core.Test.ProviderTests
         [TestCase(@"c:\Root\Test Title", @"c:\Root\_ParseError_Test Title", PostDownloadStatusType.ParseError)]
         public void GetFolderNameWithStatus_should_return_a_string_with_the_error_removing_existing_error(string currentName, string excpectedName, PostDownloadStatusType status)
         {
-            PostDownloadProvider.GetFolderNameWithStatus(new DirectoryInfo(currentName), status).Should().Be(
+            PostDownloadProvider.GetTaggedFolderName(new DirectoryInfo(currentName), status).Should().Be(
                 excpectedName);
         }
 
@@ -27,7 +27,7 @@ namespace NzbDrone.Core.Test.ProviderTests
         [ExpectedException(typeof(InvalidOperationException))]
         public void GetFolderNameWithStatus_should_throw_if_status_is_not_an_error(PostDownloadStatusType status)
         {
-            PostDownloadProvider.GetFolderNameWithStatus(new DirectoryInfo(TempFolder), status);
+            PostDownloadProvider.GetTaggedFolderName(new DirectoryInfo(TempFolder), status);
         }
 
 

NzbDrone.Core.Test/ProviderTests/PostDownloadProviderTests/ProcessDownloadFixture.cs

@@ -122,7 +122,7 @@ namespace NzbDrone.Core.Test.ProviderTests.PostDownloadProviderTests
             var mocker = new AutoMoqer(MockBehavior.Strict);
             var droppedFolder = new DirectoryInfo(@"C:\Test\Unsorted TV\The Office - Season 01");
 
-            var taggedFolder = PostDownloadProvider.GetFolderNameWithStatus(droppedFolder, PostDownloadStatusType.Unknown);
+            var taggedFolder = PostDownloadProvider.GetTaggedFolderName(droppedFolder, PostDownloadStatusType.Unknown);
 
             var fakeSeries = Builder<Series>.CreateNew()
                 .With(s => s.Title = "The Office")
@@ -147,6 +147,50 @@ namespace NzbDrone.Core.Test.ProviderTests.PostDownloadProviderTests
             ExceptionVerification.ExcpectedWarns(1);
         }
 
+        [TestCase(@"\_UnknownSeries_The Office - S01E01 - Episode Title")]
+        [TestCase(@"\_UnknownSeries_The Office - S01E01 - Episode Title\")]
+        [TestCase("\\Test\\_UnknownSeries_The Office - S01E01 - Episode Title\\")]
+        [TestCase("\\Test\\_UnknownSeries_The Office - S01E01 - Episode Title")]
+        public void folder_shouldnt_be_tagged_with_same_tag_again(string path)
+        {
+            //Setup
+            var mocker = new AutoMoqer();
+            var droppedFolder = new DirectoryInfo(TempFolder + path);
+            droppedFolder.Create();
+            droppedFolder.LastWriteTime = DateTime.Now.AddHours(-1);
+
+            //Act
+            mocker.GetMock<SeriesProvider>().Setup(s => s.FindSeries(It.IsAny<String>())).Returns<Series>(null);
+            mocker.Resolve<PostDownloadProvider>().ProcessDownload(droppedFolder);
+
+            //Assert
+            mocker.VerifyAllMocks();
+            mocker.GetMock<DiskProvider>().Verify(c => c.MoveDirectory(It.IsAny<string>(), It.IsAny<string>()), Times.Never());
+            ExceptionVerification.ExcpectedWarns(1);
+        }
+
+        [Test]
+        public void folder_should_be_tagged_if_existing_tag_is_diffrent()
+        {
+            //Setup
+            var mocker = new AutoMoqer();
+            var droppedFolder = new DirectoryInfo(TempFolder + @"\_UnknownEpisode_The Office - S01E01 - Episode Title");
+            droppedFolder.Create();
+            droppedFolder.LastWriteTime = DateTime.Now.AddHours(-1);
+
+            var taggedFolder = TempFolder + @"\_UnknownSeries_The Office - S01E01 - Episode Title";
+
+            mocker.GetMock<SeriesProvider>().Setup(s => s.FindSeries(It.IsAny<String>())).Returns<Series>(null);
+
+            //Act
+            mocker.Resolve<PostDownloadProvider>().ProcessDownload(droppedFolder);
+
+            //Assert
+            mocker.VerifyAllMocks();
+            mocker.GetMock<DiskProvider>().Verify(c => c.MoveDirectory(droppedFolder.FullName, taggedFolder), Times.Once());
+            ExceptionVerification.ExcpectedWarns(1);
+        }
+
         [Test]
         public void when_files_are_imported_and_folder_is_small_enought_dir_should_be_deleted()
         {

NzbDrone.Core/Providers/PostDownloadProvider.cs

@@ -76,7 +76,7 @@ namespace NzbDrone.Core.Providers
             {
                 if (importedFiles.Count == 0)
                 {
-                    Logger.Warn("Unable to Import new download [{0}], no importable files were found..",
+                    Logger.Warn("Unable to Import new download [{0}], no importable files were found.",
                                 subfolderInfo.Name);
                     TagFolder(subfolderInfo, PostDownloadStatusType.ParseError);
                 }
@@ -89,12 +89,17 @@ namespace NzbDrone.Core.Providers
             }
         }
 
-        public void TagFolder(DirectoryInfo directory, PostDownloadStatusType status)
+        private void TagFolder(DirectoryInfo directory, PostDownloadStatusType status)
         {
-            _diskProvider.MoveDirectory(directory.FullName, GetFolderNameWithStatus(directory, status));
+            var target = GetTaggedFolderName(directory, status);
+
+            if (!String.Equals(Parser.NormalizePath(target), Parser.NormalizePath(directory.FullName), StringComparison.InvariantCultureIgnoreCase))
+            {
+                _diskProvider.MoveDirectory(directory.FullName, target);
+            }
         }
 
-        public static string GetFolderNameWithStatus(DirectoryInfo directoryInfo, PostDownloadStatusType status)
+        public static string GetTaggedFolderName(DirectoryInfo directoryInfo, PostDownloadStatusType status)
         {
             if (status == PostDownloadStatusType.NoError)
                 throw new InvalidOperationException("Can't tag a folder with a None-error status. " + status);