All the music in my itunes library has disappeared any ideas how to get it back?

Hi bjl1767,

Thanks for visiting Apple Support Communities.

The tips in this article can help with locating your music files:

iTunes: Finding lost media and downloads

http://support.apple.com/kb/TS1408

If the music is in the iTunes Media folder on your computer, but not in your library, the iTunes library might need to be re-created:

iTunes: How to re-create your iTunes library and playlists

http://support.apple.com/kb/ht1451

Best Regards,

Jeremy