Since I installed the latest update to iTunes (11.0.4), iTunes seems to have 'lost' my library of music, and playlists. After installing the update, there is one single album in my library (there should be several days worth of music there). When I select 'show music in the cloud' I can see my iTunes purchases, and these are available for download. However, all my music is still in place on my mac, it's just not appearing in iTunes. I take it that this means that my 'library' file has become damaged? I have Time Machine backups for my system, so my question is; which file should I restore, in order to get my library and playlists back, without having to manually import all my music? I'm using OS X 10.6.8. Many thanks in advance.