Lighting failed to build. Swarm failed to kick off

Having an issue with swarm,

6:11:50 PM: [Interface:TryOpenConnection] Local connection established
6:11:50 PM: [Job] Accepted Job E231E79B-4204C649-6C0FEC9A-607151AD
6:11:56 PM: [Interface:OpenChannel] Error: System.IO.IOException: The process cannot access the file ‘D:\Dev\SVN\Unreal Engine\4.4\Engine\Binaries\DotNET\SwarmCache\AgentStagingArea\A6630D7233BF47B3BBCF76BB4350A2B5.50D8D9B84A9F415A6D610C9481C26ED9.mtrlgz’ because it is being used by another process.
at System.IO.__Error.WinIOError(Int32 errorCode, String maybeFullPath)
at System.IO.FileStream.Init(String path, FileMode mode, FileAccess access, Int32 rights, Boolean useRights, FileShare share, Int32 bufferSize, FileOptions options, SECURITY_ATTRIBUTES secAttrs, String msgPath, Boolean bFromProxy, Boolean useLongPath, Boolean checkHost)
at System.IO.FileStream…ctor(String path, FileMode mode, FileAccess access, FileShare share, Int32 bufferSize, FileOptions options, String msgPath, Boolean bFromProxy)
at System.IO.FileStream…ctor(String path, FileMode mode, FileAccess access, FileShare share)
at NSwarm.FSwarmInterface.OpenChannel(String ChannelName, EChannelFlags ChannelFlags)

Do you, by any chance, have a second instance of SwarmAgent.exe running? Maybe from a previous run that didn’t shut down properly? Please check in Windows Task Manager whether there is already an instance running, and kill it if needed.

That is something I ha e tripple checked. Even looked through my process explored and did a reboot the open ue then map then build. Same error. The interrsting thing is that this happened on my other computer also

Does this happen for all projects and maps, or only a particular one?

I can’t event test this because for no rime nor reason it started to work. the only thing different is that my PC is physically somewhere else. I will try again once I move my PC back.