With il2cpp scripting backend build system can not find the il2cppOutput file:
This step happens after the build is complete, the editor is trying to move the the C++ files generated by IL2CPP into a directory next to the the player build so that they can be used for debugging later. Is the directory in the error message writeable by the Unity process? Could there be a virus scanner program running that is locking that directory?
I have only Windows Defender, but it was disabled. I tried remove entire directory, but with clean start result was the same. Temporary solution is to copy build results to another place, before Unity is deleted them:)
I’m not sure what is happening - something must be locking that directory. In general, no other processes should have access to files or directories in the Temp/ directory, that is the scratch area where the Unity Editor does work, and it should be free to move or delete any files there at any time.
Can you use a tool like Process Explorer to catch which process might be locking that directory?