NzbDrone Epic Fail on start

Sonarr version (
Mono version (if Sonarr is not running on Windows):
Debug logs: Nothing logs
Description of issue: BOX: Epic fail - Loadfileexception: Could not load file or assembly “Microsoft.AspNet.SignalR.Core, Version=,Culture=neutral, PublicKeyToken=null” or one of its dependencies. +++

Jacket was failing to run before this, corrected with a reinstall. I have erased everything and reinstalled everything and I still get this only on Sonarr (NzbDrone.exe)


There should be a DLL with that name along side NzbDrone.exe, does it exist?

Please post the full log file.


That DLL is in the Sonarr folder and the NzbDrone folder and they are in ProgramData folder

The log file is here:

If you go to properties one that DLL is the version If you search your system for Microsoft.AspNet.SignalR.Core.dll are there other copies of in %windir%\Microsoft.NET\assembly?


There are 7 copies of this file on my machine. The highest version is 2.2.2 (Product Version) and the File Version is 2.2.60504.1171.

The one in the Sonarr folder is as above as is the NzbDrone folders is as above. There are no copies in the folder you listed.

I searched the registry and all entries for Microsoft.AspNet.SignalR.Core.dll point to version 2.2.2.


I deleted every copy of the DLL on my machine (Well archived them). Deleted the Sonarr directory. Reinstalled Sonar and at this time it is working fine.

Thanks for your efforts and help.


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