Mac build error “Copy() called does not exist”

Note: I am developing my game on Windows and it builds with IL2CPP with no errors.

Since our composer uses Mac, I wanted to also build the game on Mac, so he could also play it. Unfortunately, it gives me a weird build error and I’m not sure if it is related to FMOD or to Unity.

System.ArgumentException: Copy() calles on path that doesnt exist: “the windows unity project path”/Temp/fmod_register_static_plugins.cpp

I have no clue how it wants to look for a windows path on Mac. Am I missing something obvious?

Note:
I use github as source control and have pulled the files from github onto a macbook.
The game runs with not problems in the editor, but it doens't want to build.
The windows version is Windows 10. build 19042.985
The macOS version is High Sierra 10.13.6

 

No, I am using Github's gitignore, which adds the Library folder.

 

I have tried saving and building the fmod project to a new folder, but that didn't work.
I have deleted the Library folder so Unity builds it again. That didn't work either

 

When I start the Unity project, it even says:
FMOD: Removed temporary file Assets/Plugins/FMOD/Cache/fmod_register_static_plugins.cpp.
That is the same file it tries to read (but not in a windows path)

 

When I create a new Unity project on mac and add the FMOD plugin and even add the same FMOD project, it builds with no problem.
I also deleted all FMOD files from the project and imported new files ... still no luck

 

I got it to build by creating a completely new Unity project, importing everything from the old project and building that.