Find this one very annoying. After added all the desired music file to the itune library, all the music files will gone missng the next time i launch the itune and same to the applications, after downloaded from the app store, the next time I launch the itune all the apps will be gone in the itunes and need to do a transfer from iphone to itune. very much to me annoying is that, each time i sync, all the music file in my iphone will be gone I have to re-adding the music again to itune library!!
Can anyone here help how to retain the music file and stay there?

nope, all the while using my laptop to sync..

well guys, seems i found the answer for the 'empty library' each time i relaunch. Sony Vaio is the culprti!!! So all the Sony Vaio user pls watch out!!!!

This is due to that the Services window as 'VAIO Content Folder Watcher' will transform the Itunes. XML files into a iT.tmp file and after relaunching iTunes, the Music Library.itl was also tranformed into a tmp file and the new xml and itl were empty.

So the resolution is either :
1.stop the VCFw.exe process
2.uncheck that Vaio content folder setting

More info on this pls refer to
http://discussions.apple.com/thread.jspa?t...tart=0&tstart=0