FFLibraryUpgradeLock error while opening iMovie library from another machine I'm getting this error when opening an iMovie library that I copied from another machine. I copied it and overwrote ~/Movies/iMovie Library.imovielibrary.


  "iMovie Library” could not be opened. You don’t have permission to save the file “FFLibraryUpgradeLock” in the folder “iMovie Library


I have made sure that iMovie has "File access". I even granted iMovie full disk access.
I ended up just creating a dummy file called FFLibraryUpgradeLock inside the lib directory

$ touch ~/Movies/iMovie Library.imovielibrary/FFLibraryUpgradeLock 

and then started iMovie. Everything works fine now and I can see all the projects in the old library.