Log DownloadStation sid at Debug level to investigate possible cause reason 119.

src/NzbDrone.Core.Test/Download/DownloadClientTests/DownloadStationTests/DSMInfoProviderFixture.cs

@@ -7,11 +7,12 @@ using NzbDrone.Core.Download.Clients.DownloadStation;
 using NzbDrone.Core.Download.Clients.DownloadStation.Proxies;
 using NzbDrone.Core.Test.Framework;
 using NzbDrone.Test.Common;
+using NzbDrone.Core.Download.Clients.DownloadStation.Responses;
 
 namespace NzbDrone.Core.Test.Download.DownloadClientTests.DownloadStationTests
 {
     [TestFixture]
-    public class SerialNumberProviderFixture : CoreTest<SerialNumberProvider>
+    public class DSMInfoProviderFixture : CoreTest<DSMInfoProvider>
     {
         protected DownloadStationSettings _settings;
 
@@ -24,17 +25,27 @@ namespace NzbDrone.Core.Test.Download.DownloadClientTests.DownloadStationTests
         private void GivenValidResponse()
         {
             Mocker.GetMock<IDSMInfoProxy>()
-                  .Setup(d => d.GetSerialNumber(It.IsAny<DownloadStationSettings>()))
-                  .Returns("serial");
+                  .Setup(d => d.GetInfo(It.IsAny<DownloadStationSettings>()))
+                  .Returns(new DSMInfoResponse() { SerialNumber = "serial", Version = "DSM 6.0.1" });
         }
 
         private void GivenInvalidResponse()
         {
             Mocker.GetMock<IDSMInfoProxy>()
-                  .Setup(d => d.GetSerialNumber(It.IsAny<DownloadStationSettings>()))
+                  .Setup(d => d.GetInfo(It.IsAny<DownloadStationSettings>()))
                   .Throws(new DownloadClientException("Serial response invalid"));
         }
 
+        [Test]
+        public void should_return_version()
+        {
+            GivenValidResponse();
+
+            var version = Subject.GetDSMVersion(_settings);
+
+            version.Should().Be(new Version("6.0.1"));
+        }
+
         [Test]
         public void should_return_hashedserialnumber()
         {
@@ -46,7 +57,7 @@ namespace NzbDrone.Core.Test.Download.DownloadClientTests.DownloadStationTests
             serial.Should().Be("50DE66B735D30738618568294742FCF1DFA52A47");
 
             Mocker.GetMock<IDSMInfoProxy>()
-                  .Verify(d => d.GetSerialNumber(It.IsAny<DownloadStationSettings>()), Times.Once());
+                  .Verify(d => d.GetInfo(It.IsAny<DownloadStationSettings>()), Times.Once());
         }
 
         [Test]
@@ -60,7 +71,7 @@ namespace NzbDrone.Core.Test.Download.DownloadClientTests.DownloadStationTests
             serial2.Should().Be(serial1);
 
             Mocker.GetMock<IDSMInfoProxy>()
-                  .Verify(d => d.GetSerialNumber(It.IsAny<DownloadStationSettings>()), Times.Once());
+                  .Verify(d => d.GetInfo(It.IsAny<DownloadStationSettings>()), Times.Once());
         }
 
         [Test]

src/NzbDrone.Core.Test/Download/DownloadClientTests/DownloadStationTests/TorrentDownloadStationFixture.cs

@@ -12,6 +12,7 @@ using NzbDrone.Core.Download.Clients.DownloadStation.Proxies;
 using NzbDrone.Core.MediaFiles.TorrentInfo;
 using NzbDrone.Core.Parser.Model;
 using NzbDrone.Test.Common;
+using NzbDrone.Core.Download.Clients.DownloadStation.Responses;
 
 namespace NzbDrone.Core.Test.Download.DownloadClientTests.DownloadStationTests
 {
@@ -280,6 +281,21 @@ namespace NzbDrone.Core.Test.Download.DownloadClientTests.DownloadStationTests
               .Returns(_downloadStationConfigItems);
         }
 
+        protected void GivenApiVersions()
+        {
+            Mocker.GetMock<IDownloadStationTaskProxy>()
+                .Setup(s => s.GetApiInfo(It.IsAny<DownloadStationSettings>()))
+                .Returns(new DiskStationApiInfo() { Name = "Task", MinVersion = 1, MaxVersion = 2 });
+
+            Mocker.GetMock<IDownloadStationInfoProxy>()
+                .Setup(s => s.GetApiInfo(It.IsAny<DownloadStationSettings>()))
+                .Returns(new DiskStationApiInfo() { Name = "Info", MinVersion = 1, MaxVersion = 3 });
+
+            Mocker.GetMock<IFileStationProxy>()
+                .Setup(s => s.GetApiInfo(It.IsAny<DownloadStationSettings>()))
+                .Returns(new DiskStationApiInfo() { Name = "File", MinVersion = 1, MaxVersion = 2 });
+        }
+
         protected void GivenSharedFolder()
         {
             Mocker.GetMock<ISharedFolderResolver>()
@@ -289,7 +305,7 @@ namespace NzbDrone.Core.Test.Download.DownloadClientTests.DownloadStationTests
 
         protected void GivenSerialNumber()
         {
-            Mocker.GetMock<ISerialNumberProvider>()
+            Mocker.GetMock<IDSMInfoProvider>()
                 .Setup(s => s.GetSerialNumber(It.IsAny<DownloadStationSettings>()))
                 .Returns(_serialNumber);
         }
@@ -359,6 +375,26 @@ namespace NzbDrone.Core.Test.Download.DownloadClientTests.DownloadStationTests
             return tasks.Count;
         }
 
+
+        protected void GivenDSMVersion(string version)
+        {
+            Mocker.GetMock<IDSMInfoProvider>()
+                .Setup(d => d.GetDSMVersion(It.IsAny<DownloadStationSettings>()))
+                .Returns(new Version(version));
+        }
+
+        [TestCase("6.0.0", 0)]
+        [TestCase("5.0.0", 1)]
+        public void TestConnection_should_return_validation_failure_as_expected(string version, int count)
+        {
+            GivenApiVersions();
+            GivenDSMVersion(version);
+
+            var result = Subject.Test();
+
+            result.Errors.Should().HaveCount(count);
+        }
+
         [Test]
         public void Download_with_TvDirectory_should_force_directory()
         {
@@ -460,7 +496,7 @@ namespace NzbDrone.Core.Test.Download.DownloadClientTests.DownloadStationTests
         [Test]
         public void GetItems_should_throw_if_serial_number_unavailable()
         {
-            Mocker.GetMock<ISerialNumberProvider>()
+            Mocker.GetMock<IDSMInfoProvider>()
                   .Setup(s => s.GetSerialNumber(_settings))
                   .Throws(new ApplicationException("Some unknown exception, HttpException or DownloadClientException"));
 
@@ -476,7 +512,7 @@ namespace NzbDrone.Core.Test.Download.DownloadClientTests.DownloadStationTests
         {
             var remoteEpisode = CreateRemoteEpisode();
 
-            Mocker.GetMock<ISerialNumberProvider>()
+            Mocker.GetMock<IDSMInfoProvider>()
                   .Setup(s => s.GetSerialNumber(_settings))
                   .Throws(new ApplicationException("Some unknown exception, HttpException or DownloadClientException"));
 

src/NzbDrone.Core.Test/Download/DownloadClientTests/DownloadStationTests/UsenetDownloadStationFixture.cs

@@ -182,6 +182,21 @@ namespace NzbDrone.Core.Test.Download.DownloadClientTests.DownloadStationTests
               .Returns(_downloadStationConfigItems);
         }
 
+        protected void GivenApiVersions()
+        {
+            Mocker.GetMock<IDownloadStationTaskProxy>()
+                .Setup(s => s.GetApiInfo(It.IsAny<DownloadStationSettings>()))
+                .Returns(new DiskStationApiInfo() { Name = "Task", MinVersion = 1, MaxVersion = 2 });
+
+            Mocker.GetMock<IDownloadStationInfoProxy>()
+                .Setup(s => s.GetApiInfo(It.IsAny<DownloadStationSettings>()))
+                .Returns(new DiskStationApiInfo() { Name = "Info", MinVersion = 1, MaxVersion = 3 });
+
+            Mocker.GetMock<IFileStationProxy>()
+                .Setup(s => s.GetApiInfo(It.IsAny<DownloadStationSettings>()))
+                .Returns(new DiskStationApiInfo() { Name = "File", MinVersion = 1, MaxVersion = 2 });
+        }
+
         protected void GivenSharedFolder()
         {
             Mocker.GetMock<ISharedFolderResolver>()
@@ -191,7 +206,7 @@ namespace NzbDrone.Core.Test.Download.DownloadClientTests.DownloadStationTests
 
         protected void GivenSerialNumber()
         {
-            Mocker.GetMock<ISerialNumberProvider>()
+            Mocker.GetMock<IDSMInfoProvider>()
                 .Setup(s => s.GetSerialNumber(It.IsAny<DownloadStationSettings>()))
                 .Returns(_serialNumber);
         }
@@ -245,6 +260,25 @@ namespace NzbDrone.Core.Test.Download.DownloadClientTests.DownloadStationTests
             Mocker.GetMock<IDownloadStationTaskProxy>()
                   .Setup(d => d.GetTasks(_settings))
                   .Returns(tasks);
+		}
+
+ 		protected void GivenDSMVersion(string version)
+        {
+            Mocker.GetMock<IDSMInfoProvider>()
+                .Setup(d => d.GetDSMVersion(It.IsAny<DownloadStationSettings>()))
+                .Returns(new Version(version));
+        }
+
+        [TestCase("6.0.0", 0)]
+        [TestCase("5.0.0", 1)]
+        public void TestConnection_should_return_validation_failure_as_expected(string version, int count)
+        {
+            GivenApiVersions();
+            GivenDSMVersion(version);
+
+            var result = Subject.Test();
+
+            result.Errors.Should().HaveCount(count);
         }
 
         [Test]
@@ -348,7 +382,7 @@ namespace NzbDrone.Core.Test.Download.DownloadClientTests.DownloadStationTests
         [Test]
         public void GetItems_should_throw_if_serial_number_unavailable()
         {
-            Mocker.GetMock<ISerialNumberProvider>()
+            Mocker.GetMock<IDSMInfoProvider>()
                   .Setup(s => s.GetSerialNumber(_settings))
                   .Throws(new ApplicationException("Some unknown exception, HttpException or DownloadClientException"));
 
@@ -364,7 +398,7 @@ namespace NzbDrone.Core.Test.Download.DownloadClientTests.DownloadStationTests
         {
             var remoteEpisode = CreateRemoteEpisode();
 
-            Mocker.GetMock<ISerialNumberProvider>()
+            Mocker.GetMock<IDSMInfoProvider>()
                   .Setup(s => s.GetSerialNumber(_settings))
                   .Throws(new ApplicationException("Some unknown exception, HttpException or DownloadClientException"));
 

src/NzbDrone.Core.Test/Housekeeping/Housekeepers/FixFutureDownloadClientStatusTimesFixture.cs

@@ -60,7 +60,7 @@ namespace NzbDrone.Core.Test.Housekeeping.Housekeepers
             Mocker.GetMock<IDownloadClientStatusRepository>()
                   .Verify(v => v.UpdateMany(
                           It.Is<List<DownloadClientStatus>>(i => i.All(
-                              s => s.InitialFailure.Value < DateTime.UtcNow))
+                              s => s.InitialFailure.Value <= DateTime.UtcNow))
                       )
                   );
         }
@@ -85,7 +85,7 @@ namespace NzbDrone.Core.Test.Housekeeping.Housekeepers
             Mocker.GetMock<IDownloadClientStatusRepository>()
                   .Verify(v => v.UpdateMany(
                           It.Is<List<DownloadClientStatus>>(i => i.All(
-                              s => s.MostRecentFailure.Value < DateTime.UtcNow))
+                              s => s.MostRecentFailure.Value <= DateTime.UtcNow))
                       )
                   );
         }

src/NzbDrone.Core.Test/NzbDrone.Core.Test.csproj

@@ -176,7 +176,7 @@
     <Compile Include="Download\DownloadClientTests\DelugeTests\DelugeFixture.cs" />
     <Compile Include="Download\DownloadClientTests\DownloadClientFixtureBase.cs" />
     <Compile Include="Download\DownloadClientTests\DownloadStationTests\TorrentDownloadStationFixture.cs" />
-    <Compile Include="Download\DownloadClientTests\DownloadStationTests\SerialNumberProviderFixture.cs" />
+    <Compile Include="Download\DownloadClientTests\DownloadStationTests\DSMInfoProviderFixture.cs" />
     <Compile Include="Download\DownloadClientTests\DownloadStationTests\SharedFolderResolverFixture.cs" />
     <Compile Include="Download\DownloadClientTests\DownloadStationTests\UsenetDownloadStationFixture.cs" />
     <Compile Include="Download\DownloadClientTests\HadoukenTests\HadoukenFixture.cs" />

src/NzbDrone.Core/Download/Clients/DownloadStation/DSMInfoProvider.cs

@@ -0,0 +1,62 @@
+using System;
+using System.Text.RegularExpressions;
+using NLog;
+using NzbDrone.Common.Cache;
+using NzbDrone.Common.Crypto;
+using NzbDrone.Common.Extensions;
+using NzbDrone.Core.Download.Clients.DownloadStation.Proxies;
+using NzbDrone.Core.Download.Clients.DownloadStation.Responses;
+
+namespace NzbDrone.Core.Download.Clients.DownloadStation
+{
+    public interface IDSMInfoProvider
+    {
+        string GetSerialNumber(DownloadStationSettings settings);
+        Version GetDSMVersion(DownloadStationSettings settings);
+    }
+
+    public class DSMInfoProvider : IDSMInfoProvider
+    {
+        private readonly IDSMInfoProxy _proxy;
+        private ICached<DSMInfoResponse> _cache;
+        private readonly ILogger _logger;
+
+        public DSMInfoProvider(ICacheManager cacheManager,
+                                    IDSMInfoProxy proxy,
+                                    Logger logger)
+        {
+            _proxy = proxy;
+            _cache = cacheManager.GetCache<DSMInfoResponse>(GetType());
+            _logger = logger;
+        }
+
+        private DSMInfoResponse GetInfo(DownloadStationSettings settings)
+        {
+            return _cache.Get(settings.Host, () => _proxy.GetInfo(settings), TimeSpan.FromMinutes(5));
+        }
+
+        public string GetSerialNumber(DownloadStationSettings settings)
+        {
+            try
+            {
+                return HashConverter.GetHash(GetInfo(settings).SerialNumber).ToHexString();
+            }
+            catch (Exception ex)
+            {
+                _logger.Warn(ex, "Could not get the serial number from Download Station {0}:{1}", settings.Host, settings.Port);
+                throw;
+            }
+        }
+
+        public Version GetDSMVersion(DownloadStationSettings settings)
+        {
+            var info = GetInfo(settings);
+
+            Regex regex = new Regex(@"DSM (?<version>[\d.]*)");
+
+            var dsmVersion = regex.Match(info.Version).Groups["version"].Value;
+
+            return new Version(dsmVersion);
+        }
+    }
+}

src/NzbDrone.Core/Download/Clients/DownloadStation/DownloadStationTask.cs

@@ -1,5 +1,4 @@
-using System;
-using System.Collections.Generic;
+using System.Collections.Generic;
 using Newtonsoft.Json;
 using Newtonsoft.Json.Converters;
 

src/NzbDrone.Core/Download/Clients/DownloadStation/DownloadStationTaskAdditional.cs

@@ -1,5 +1,5 @@
-using Newtonsoft.Json;
-using System.Collections.Generic;
+using System.Collections.Generic;
+using Newtonsoft.Json;
 
 namespace NzbDrone.Core.Download.Clients.DownloadStation
 {

src/NzbDrone.Core/Download/Clients/DownloadStation/DownloadStationTaskFile.cs

@@ -1,10 +1,5 @@
 using Newtonsoft.Json;
 using Newtonsoft.Json.Converters;
-using System;
-using System.Collections.Generic;
-using System.Linq;
-using System.Text;
-using static NzbDrone.Core.Download.Clients.DownloadStation.DownloadStationTask;
 
 namespace NzbDrone.Core.Download.Clients.DownloadStation
 {

src/NzbDrone.Core/Download/Clients/DownloadStation/Proxies/DSMInfoProxy.cs

@@ -1,15 +1,13 @@
-using System;
-using System.Collections.Generic;
-using NLog;
+using NLog;
 using NzbDrone.Common.Cache;
 using NzbDrone.Common.Http;
 using NzbDrone.Core.Download.Clients.DownloadStation.Responses;
 
 namespace NzbDrone.Core.Download.Clients.DownloadStation.Proxies
 {
-    public interface IDSMInfoProxy
+    public interface IDSMInfoProxy : IDiskStationProxy
     {
-        string GetSerialNumber(DownloadStationSettings settings);
+        DSMInfoResponse GetInfo(DownloadStationSettings settings);
     }
 
     public class DSMInfoProxy : DiskStationProxyBase, IDSMInfoProxy
@@ -19,15 +17,15 @@ namespace NzbDrone.Core.Download.Clients.DownloadStation.Proxies
         {
         }
 
-        public string GetSerialNumber(DownloadStationSettings settings)
+        public DSMInfoResponse GetInfo(DownloadStationSettings settings)
         {
             var info = GetApiInfo(settings);
 
             var requestBuilder = BuildRequest(settings, "getinfo", info.MinVersion);
 
-            var response = ProcessRequest<DSMInfoResponse>(requestBuilder, "get serial number", settings);
+            var response = ProcessRequest<DSMInfoResponse>(requestBuilder, "get info", settings);
 
-            return response.Data.SerialNumber;
+            return response.Data;
         }
     }
 }

src/NzbDrone.Core/Download/Clients/DownloadStation/Proxies/DiskStationProxyBase.cs

@@ -1,6 +1,5 @@
 using System;
 using System.Collections.Generic;
-using System.Linq;
 using System.Net;
 using NLog;
 using NzbDrone.Common.Cache;
@@ -161,7 +160,9 @@ namespace NzbDrone.Core.Download.Clients.DownloadStation.Proxies
             {
                 if (apiInfo.NeedsAuthentication)
                 {
-                    requestBuilder.AddFormParameter("_sid", _sessionCache.Get(GenerateSessionCacheKey(settings), () => AuthenticateClient(settings), TimeSpan.FromHours(6)));
+                    var sid = _sessionCache.Get(GenerateSessionCacheKey(settings), () => AuthenticateClient(settings), TimeSpan.FromHours(6));
+                    _logger.Debug("DownloadStation Session sid={0}", sid);
+                    requestBuilder.AddFormParameter("_sid", sid);
                 }
 
                 requestBuilder.AddFormParameter("api", apiInfo.Name);
@@ -172,7 +173,9 @@ namespace NzbDrone.Core.Download.Clients.DownloadStation.Proxies
             {
                 if (apiInfo.NeedsAuthentication)
                 {
-                    requestBuilder.AddQueryParam("_sid", _sessionCache.Get(GenerateSessionCacheKey(settings), () => AuthenticateClient(settings), TimeSpan.FromHours(6)));
+                    var sid = _sessionCache.Get(GenerateSessionCacheKey(settings), () => AuthenticateClient(settings), TimeSpan.FromHours(6));
+                    _logger.Debug("DownloadStation Session sid={0}", sid);
+                    requestBuilder.AddQueryParam("_sid", sid);
                 }
 
                 requestBuilder.AddQueryParam("api", apiInfo.Name);

src/NzbDrone.Core/Download/Clients/DownloadStation/Proxies/DownloadStationInfoProxy.cs

@@ -1,7 +1,7 @@
-using NLog;
-using NzbDrone.Common.Http;
-using System.Collections.Generic;
+using System.Collections.Generic;
+using NLog;
 using NzbDrone.Common.Cache;
+using NzbDrone.Common.Http;
 
 namespace NzbDrone.Core.Download.Clients.DownloadStation.Proxies
 {

src/NzbDrone.Core/Download/Clients/DownloadStation/Proxies/ExpectedVersion.cs

@@ -0,0 +1,8 @@
+namespace NzbDrone.Core.Download.Clients.DownloadStation.Proxies
+{
+    public class ExpectedVersion
+    {
+        public int Version { get; set; }
+        public IDiskStationProxy Proxy { get; set; }
+    }
+}

src/NzbDrone.Core/Download/Clients/DownloadStation/Proxies/FileStationProxy.cs

@@ -1,5 +1,4 @@
 using System;
-using System.Collections.Generic;
 using System.Linq;
 using NLog;
 using NzbDrone.Common.Cache;
@@ -18,9 +17,15 @@ namespace NzbDrone.Core.Download.Clients.DownloadStation.Proxies
 
     public class FileStationProxy : DiskStationProxyBase, IFileStationProxy
     {
-        public FileStationProxy(IHttpClient httpClient, ICacheManager cacheManager, Logger logger)
+        private IDSMInfoProvider _dsmInfoProvider;
+
+        public FileStationProxy(IDSMInfoProvider dsmInfoProvider,
+                                IHttpClient httpClient,
+                                ICacheManager cacheManager,
+                                Logger logger)
             : base(DiskStationApi.FileStationList, "SYNO.FileStation.List", httpClient, cacheManager, logger)
         {
+            _dsmInfoProvider = dsmInfoProvider;
         }
 
         public SharedFolderMapping GetSharedFolderMapping(string sharedFolder, DownloadStationSettings settings)
@@ -34,13 +39,16 @@ namespace NzbDrone.Core.Download.Clients.DownloadStation.Proxies
 
         public FileStationListFileInfoResponse GetInfoFileOrDirectory(string path, DownloadStationSettings settings)
         {
-            var requestBuilder = BuildRequest(settings, "getinfo", 2);
+            var dsmVersion = _dsmInfoProvider.GetDSMVersion(settings);
+
+            var requestBuilder = BuildRequest(settings, "getinfo", dsmVersion >= new Version(6, 0, 0) ? 2 : 1);
             requestBuilder.AddQueryParam("path", new[] { path }.ToJson());
             requestBuilder.AddQueryParam("additional", "[\"real_path\"]");
 
             var response = ProcessRequest<FileStationListResponse>(requestBuilder, $"get info of {path}", settings);
 
             return response.Data.Files.First();
+
         }
     }
 }

src/NzbDrone.Core/Download/Clients/DownloadStation/Responses/DSMInfoResponse.cs

@@ -6,5 +6,8 @@ namespace NzbDrone.Core.Download.Clients.DownloadStation.Responses
     {
         [JsonProperty("serial")]
         public string SerialNumber { get; set; }
+
+        [JsonProperty("version_string")]
+        public string Version { get; set; }
     }
 }

src/NzbDrone.Core/Download/Clients/DownloadStation/SerialNumberProvider.cs

@@ -1,49 +0,0 @@
-using System;
-using NLog;
-using NzbDrone.Common.Cache;
-using NzbDrone.Common.Crypto;
-using NzbDrone.Common.Extensions;
-using NzbDrone.Core.Download.Clients.DownloadStation.Proxies;
-
-namespace NzbDrone.Core.Download.Clients.DownloadStation
-{
-    public interface ISerialNumberProvider
-    {
-        string GetSerialNumber(DownloadStationSettings settings);
-    }
-
-    public class SerialNumberProvider : ISerialNumberProvider
-    {
-        private readonly IDSMInfoProxy _proxy;
-        private ICached<string> _cache;
-        private readonly ILogger _logger;
-
-        public SerialNumberProvider(ICacheManager cacheManager,
-                                    IDSMInfoProxy proxy,
-                                    Logger logger)
-        {
-            _proxy = proxy;
-            _cache = cacheManager.GetCache<string>(GetType());
-            _logger = logger;
-        }
-
-        public string GetSerialNumber(DownloadStationSettings settings)
-        {
-            try
-            {
-                return _cache.Get(settings.Host, () => GetHashedSerialNumber(settings), TimeSpan.FromMinutes(5));
-            }
-            catch (Exception ex)
-            {
-                _logger.Warn(ex, "Could not get the serial number from Download Station {0}:{1}", settings.Host, settings.Port);
-                throw;
-            }
-        }
-
-        private string GetHashedSerialNumber(DownloadStationSettings settings)
-        {
-            var serialNumber = _proxy.GetSerialNumber(settings);
-            return HashConverter.GetHash(serialNumber).ToHexString();
-        }
-    }
-}

src/NzbDrone.Core/Download/Clients/DownloadStation/TorrentDownloadStation.cs

@@ -22,11 +22,11 @@ namespace NzbDrone.Core.Download.Clients.DownloadStation
         protected readonly IDownloadStationInfoProxy _dsInfoProxy;
         protected readonly IDownloadStationTaskProxy _dsTaskProxy;
         protected readonly ISharedFolderResolver _sharedFolderResolver;
-        protected readonly ISerialNumberProvider _serialNumberProvider;
+        protected readonly IDSMInfoProvider _dsmInfoProvider;
         protected readonly IFileStationProxy _fileStationProxy;
         
         public TorrentDownloadStation(ISharedFolderResolver sharedFolderResolver,
-                                      ISerialNumberProvider serialNumberProvider,
+                                      IDSMInfoProvider dsmInfoProvider,
                                       IFileStationProxy fileStationProxy,
                                       IDownloadStationInfoProxy dsInfoProxy,
                                       IDownloadStationTaskProxy dsTaskProxy,
@@ -42,7 +42,7 @@ namespace NzbDrone.Core.Download.Clients.DownloadStation
             _dsTaskProxy = dsTaskProxy;
             _fileStationProxy = fileStationProxy;
             _sharedFolderResolver = sharedFolderResolver;
-            _serialNumberProvider = serialNumberProvider;
+            _dsmInfoProvider = dsmInfoProvider;
         }
 
         public override string Name => "Download Station";
@@ -55,7 +55,7 @@ namespace NzbDrone.Core.Download.Clients.DownloadStation
         public override IEnumerable<DownloadClientItem> GetItems()
         {
             var torrents = GetTasks();
-            var serialNumber = _serialNumberProvider.GetSerialNumber(Settings);
+            var serialNumber = _dsmInfoProvider.GetSerialNumber(Settings);
 
             var items = new List<DownloadClientItem>();
 
@@ -149,7 +149,7 @@ namespace NzbDrone.Core.Download.Clients.DownloadStation
 
         protected override string AddFromMagnetLink(RemoteEpisode remoteEpisode, string hash, string magnetLink)
         {
-            var hashedSerialNumber = _serialNumberProvider.GetSerialNumber(Settings);
+            var hashedSerialNumber = _dsmInfoProvider.GetSerialNumber(Settings);
 
             _dsTaskProxy.AddTaskFromUrl(magnetLink, GetDownloadDirectory(), Settings);
 
@@ -168,7 +168,7 @@ namespace NzbDrone.Core.Download.Clients.DownloadStation
 
         protected override string AddFromTorrentFile(RemoteEpisode remoteEpisode, string hash, string filename, byte[] fileContent)
         {
-            var hashedSerialNumber = _serialNumberProvider.GetSerialNumber(Settings);
+            var hashedSerialNumber = _dsmInfoProvider.GetSerialNumber(Settings);
 
             _dsTaskProxy.AddTaskFromData(fileContent, filename, GetDownloadDirectory(), Settings);
 
@@ -191,6 +191,7 @@ namespace NzbDrone.Core.Download.Clients.DownloadStation
         {
             failures.AddIfNotNull(TestConnection());
             if (failures.Any()) return;
+            failures.AddIfNotNull(TestDSMVersion());
             failures.AddIfNotNull(TestOutputPath());
             failures.AddIfNotNull(TestGetTorrents());
         }
@@ -303,7 +304,7 @@ namespace NzbDrone.Core.Download.Clients.DownloadStation
                     {
                         return new NzbDroneValidationFailure(fieldName, $"Shared folder does not exist")
                         {
-                            DetailedDescription = $"The Diskstation does not have a Shared Folder with the name '{sharedFolder}', are you sure you specified it correctly?"
+                            DetailedDescription = $"The Diskstation does not have a Shared Folder with the name '{downloadDir}', are you sure you specified it correctly?"
                         };
                     }
 
@@ -334,7 +335,7 @@ namespace NzbDrone.Core.Download.Clients.DownloadStation
         {
             try
             {
-                return ValidateVersion();
+                return TestProxiesVersions();
             }
             catch (DownloadClientAuthenticationException ex)
             {
@@ -364,15 +365,39 @@ namespace NzbDrone.Core.Download.Clients.DownloadStation
             }
         }
         
-        protected ValidationFailure ValidateVersion()
+        protected ValidationFailure TestDSMVersion()
         {
-            var info = _dsTaskProxy.GetApiInfo(Settings);
+            var dsmversion = _dsmInfoProvider.GetDSMVersion(Settings);
 
-            _logger.Debug("Download Station api version information: Min {0} - Max {1}", info.MinVersion, info.MaxVersion);
-
-            if (info.MinVersion > 2 || info.MaxVersion < 2)
+            if (dsmversion < new Version(6, 0, 0))
             {
-                return new ValidationFailure(string.Empty, $"Download Station API version not supported, should be at least 2. It supports from {info.MinVersion} to {info.MaxVersion}");
+                return new NzbDroneValidationFailure(string.Empty, $"DSM Version {dsmversion} not fully supported. We recommend version 6.0.0 or above.") { IsWarning = true };
+            }
+
+            return null;
+        }
+
+        protected ValidationFailure TestProxiesVersions()
+        {
+            var dsmVersion = _dsmInfoProvider.GetDSMVersion(Settings);
+
+            var expectedVersions = new List<ExpectedVersion>()
+            {
+                new ExpectedVersion { Version = 2, Proxy = _dsTaskProxy },
+                new ExpectedVersion { Version = (dsmVersion >= new Version(6,0,0))? 2 : 1, Proxy = _fileStationProxy },
+                new ExpectedVersion { Version = 1, Proxy = _dsInfoProxy }
+            };
+
+            foreach (var expectedVersion in expectedVersions)
+            {
+                DiskStationApiInfo apiInfo = expectedVersion.Proxy.GetApiInfo(Settings);
+
+                _logger.Debug("{1} api version information: Min {1} - Max {2} - Expected {3}", apiInfo.Name, apiInfo.MinVersion, apiInfo.MaxVersion, expectedVersion.Version);
+
+                if (apiInfo.MinVersion > expectedVersion.Version || apiInfo.MaxVersion < expectedVersion.Version)
+                {
+                    return new NzbDroneValidationFailure(string.Empty, $"{apiInfo.Name} API version not supported, should be at least {expectedVersion.Version}. It supports from {apiInfo.MinVersion} to {apiInfo.MaxVersion}");
+                }
             }
 
             return null;

src/NzbDrone.Core/Download/Clients/DownloadStation/UsenetDownloadStation.cs

@@ -20,11 +20,11 @@ namespace NzbDrone.Core.Download.Clients.DownloadStation
         protected readonly IDownloadStationInfoProxy _dsInfoProxy;
         protected readonly IDownloadStationTaskProxy _dsTaskProxy;
         protected readonly ISharedFolderResolver _sharedFolderResolver;
-        protected readonly ISerialNumberProvider _serialNumberProvider;
+        protected readonly IDSMInfoProvider _dsmInfoProvider;
         protected readonly IFileStationProxy _fileStationProxy;
 
         public UsenetDownloadStation(ISharedFolderResolver sharedFolderResolver,
-                                     ISerialNumberProvider serialNumberProvider,
+                                     IDSMInfoProvider dsmInfoProvider,
                                      IFileStationProxy fileStationProxy,
                                      IDownloadStationInfoProxy dsInfoProxy,
                                      IDownloadStationTaskProxy dsTaskProxy,
@@ -40,7 +40,7 @@ namespace NzbDrone.Core.Download.Clients.DownloadStation
             _dsTaskProxy = dsTaskProxy;
             _fileStationProxy = fileStationProxy;
             _sharedFolderResolver = sharedFolderResolver;
-            _serialNumberProvider = serialNumberProvider;
+            _dsmInfoProvider = dsmInfoProvider;
         }
 
         public override string Name => "Download Station";
@@ -53,7 +53,7 @@ namespace NzbDrone.Core.Download.Clients.DownloadStation
         public override IEnumerable<DownloadClientItem> GetItems()
         {
             var nzbTasks = GetTasks();
-            var serialNumber = _serialNumberProvider.GetSerialNumber(Settings);
+            var serialNumber = _dsmInfoProvider.GetSerialNumber(Settings);
 
             var items = new List<DownloadClientItem>();
 
@@ -163,7 +163,7 @@ namespace NzbDrone.Core.Download.Clients.DownloadStation
 
         protected override string AddFromNzbFile(RemoteEpisode remoteEpisode, string filename, byte[] fileContent)
         {
-            var hashedSerialNumber = _serialNumberProvider.GetSerialNumber(Settings);
+            var hashedSerialNumber = _dsmInfoProvider.GetSerialNumber(Settings);
 
             _dsTaskProxy.AddTaskFromData(fileContent, filename, GetDownloadDirectory(), Settings);
 
@@ -186,6 +186,7 @@ namespace NzbDrone.Core.Download.Clients.DownloadStation
         {
             failures.AddIfNotNull(TestConnection());
             if (failures.Any()) return;
+            failures.AddIfNotNull(TestDSMVersion());
             failures.AddIfNotNull(TestOutputPath());
             failures.AddIfNotNull(TestGetNZB());
         }
@@ -217,7 +218,7 @@ namespace NzbDrone.Core.Download.Clients.DownloadStation
                     {
                         return new NzbDroneValidationFailure(fieldName, $"Shared folder does not exist")
                         {
-                            DetailedDescription = $"The Diskstation does not have a Shared Folder with the name '{sharedFolder}', are you sure you specified it correctly?"
+                            DetailedDescription = $"The Diskstation does not have a Shared Folder with the name '{downloadDir}', are you sure you specified it correctly?"
                         };
                     }
 
@@ -248,7 +249,7 @@ namespace NzbDrone.Core.Download.Clients.DownloadStation
         {
             try
             {
-                return ValidateVersion();
+                return TestProxiesVersions();
             }
             catch (DownloadClientAuthenticationException ex)
             {
@@ -269,24 +270,48 @@ namespace NzbDrone.Core.Download.Clients.DownloadStation
                         DetailedDescription = "Please verify the hostname and port."
                     };
                 }
-                return new NzbDroneValidationFailure(string.Empty, "Unknown exception: " + ex.Message);
+                return new NzbDroneValidationFailure(string.Empty, $"Unknown exception: {ex.Message}");
             }
             catch (Exception ex)
             {
                 _logger.Error(ex, "Error testing Torrent Download Station");
-                return new NzbDroneValidationFailure(string.Empty, "Unknown exception: " + ex.Message);
+                return new NzbDroneValidationFailure(string.Empty, $"Unknown exception: {ex.Message}");
             }
         }
         
-        protected ValidationFailure ValidateVersion()
+        protected ValidationFailure TestDSMVersion()
         {
-            var info = _dsTaskProxy.GetApiInfo(Settings);
+            var dsmversion = _dsmInfoProvider.GetDSMVersion(Settings);
 
-            _logger.Debug("Download Station api version information: Min {0} - Max {1}", info.MinVersion, info.MaxVersion);
-
-            if (info.MinVersion > 2 || info.MaxVersion < 2)
+            if (dsmversion < new Version(6, 0, 0))
             {
-                return new ValidationFailure(string.Empty, $"Download Station API version not supported, should be at least 2. It supports from {info.MinVersion} to {info.MaxVersion}");
+                return new NzbDroneValidationFailure(string.Empty, $"DSM Version {dsmversion} not fully supported. We recommend version 6.0.0 or above.") { IsWarning = true };
+            }
+
+            return null;
+        }
+
+        protected ValidationFailure TestProxiesVersions()
+        {
+            var dsmVersion = _dsmInfoProvider.GetDSMVersion(Settings);
+
+            var expectedVersions = new List<ExpectedVersion>()
+            {
+                new ExpectedVersion { Version = 2, Proxy = _dsTaskProxy },
+                new ExpectedVersion { Version = (dsmVersion >= new Version(6,0,0))? 2 : 1, Proxy = _fileStationProxy },
+                new ExpectedVersion { Version = 1, Proxy = _dsInfoProxy }
+            };
+
+            foreach (var expectedVersion in expectedVersions)
+            {
+                DiskStationApiInfo apiInfo = expectedVersion.Proxy.GetApiInfo(Settings);
+
+                _logger.Debug("{1} api version information: Min {1} - Max {2} - Expected {3}", apiInfo.Name, apiInfo.MinVersion, apiInfo.MaxVersion, expectedVersion.Version);
+
+                if (apiInfo.MinVersion > expectedVersion.Version || apiInfo.MaxVersion < expectedVersion.Version)
+                {
+                    return new NzbDroneValidationFailure(string.Empty, $"{apiInfo.Name} API version not supported, should be at least {expectedVersion.Version}. It supports from {apiInfo.MinVersion} to {apiInfo.MaxVersion}");
+                }
             }
 
             return null;
@@ -377,7 +402,7 @@ namespace NzbDrone.Core.Download.Clients.DownloadStation
             }
             catch (Exception ex)
             {
-                return new NzbDroneValidationFailure(string.Empty, "Failed to get the list of NZBs: " + ex.Message);
+                return new NzbDroneValidationFailure(string.Empty, $"Failed to get the list of NZBs: {ex.Message}");
             }
         }
 

src/NzbDrone.Core/NzbDrone.Core.csproj

@@ -371,7 +371,9 @@
     <Compile Include="Download\Clients\DownloadClientAuthenticationException.cs" />
     <Compile Include="Download\Clients\DownloadClientUnavailableException.cs" />
     <Compile Include="Download\Clients\DownloadClientException.cs" />
+    <Compile Include="Download\Clients\DownloadStation\DSMInfoProvider.cs" />
     <Compile Include="Download\Clients\DownloadStation\Proxies\DownloadStationInfoProxy.cs" />
+    <Compile Include="Download\Clients\DownloadStation\Proxies\ExpectedVersion.cs" />
     <Compile Include="Download\Clients\DownloadStation\TorrentDownloadStation.cs" />
     <Compile Include="Download\Clients\DownloadStation\Proxies\DownloadStationTaskProxy.cs" />
     <Compile Include="Download\Clients\DownloadStation\DownloadStationSettings.cs" />
@@ -390,7 +392,6 @@
     <Compile Include="Download\Clients\DownloadStation\Responses\DiskStationResponse.cs" />
     <Compile Include="Download\Clients\DownloadStation\Responses\DownloadStationTaskInfoResponse.cs" />
     <Compile Include="Download\Clients\DownloadStation\DiskStationApiInfo.cs" />
-    <Compile Include="Download\Clients\DownloadStation\SerialNumberProvider.cs" />
     <Compile Include="Download\Clients\DownloadStation\SharedFolderMapping.cs" />
     <Compile Include="Download\Clients\DownloadStation\SharedFolderResolver.cs" />
     <Compile Include="Download\Clients\DownloadStation\DiskStationApi.cs" />