Music Folder Can't be accessed

Just downloaded EP 1.5.1 under Mac OS 10.15 on a new Macbook On launch this error, only option is to exit Anyone know what’s up?

OK I can answer my own question but I’ll leave it here in case useful to others. The problem seems to have an aborted attempt to transfer the library from my old laptop. I deleted the library and then Prime opened.

Just make another music folder, i made mine on desktop and in C drive and both worked well. Hope this helps