iTunes library file damaged after manual migration to new Mac On my old computer, I had the following setup:


iTunes Folder containing iTunes Library.itl on my main hard disk (~/Music/iTunes)
Music folder on a second HD where all the actual music files lived (I had checked "Keep library organized").


My new laptop has only one HD, so manually I copied the Music Folder (2) to the new HD and put the iTunes Library.itl, iTunes Library Extras and iTunes Library Genius into it (both from a time machine backup). 

Opening iTunes brings up a blank library. When I open iTunes by clicking the app icon while holding alt, choose the library it says: 


  iTunes library is not valid. iTunes has created a new library and renamed the original to "iTunes library (damaged)".


(translated from German)

I am using Apple Music, too. Am I missing something?
As user33958 has pointed out, iTunes Library.xml needs to be copied too.