UE4 Git Source Build Fail (MSB3075)

UE 4.20.3. I have previous been building UE4 from source without any issues when last night I received the following error when trying to build the vanilla UE4 editor in VS 2017

  • /Path/UE is not a recognised command
  • operable program or batch file.
  • Custom build step terminated with
    exit code 1
  • MSB3075 The Command
    ShaderCompilerWorker Win64
    Development -WaitMutex -FromMsBuild”
    Exited with code 5. Please verify
    that you have sufficient rights to
    run this command

I’ve tried normal troubleshooting steps with no success, including downing a completely fresh release branch from the Epic Games GIT.

This started happening after I rebuilt by project, but now seems to affect completely freshly downloaded release branch versions. I’ve followed all the steps down to the wire but with no success.

Is there any settings in VS 2017 I should be cautious around? What does it mean around rights? I have not changed any admin settings etc.