Navigate to the folder containing your music and import your library back into i Tunes.
Click "File" in the i Tunes application window, select the music files you want to import and press "Enter."Force i Tunes to look for your songs and import them manually if the above method fails to recover your lost music.
There are still things to do after you updating your device to i OS 8.
You may need to restore data such as contacts, notes, calendar, music, photos to your device; transfer data from the computer or an old device to your present one; speed up your device to smoothly run the new i OS 8; learn some useful tips on how to extend battery life of your device.
i Tunes puts an exclamation point next to content in i Tunes when it can't find a file.
i Tunes might not be able to find a file or folder if: Information about products not manufactured by Apple, or independent websites not controlled or tested by Apple, is provided without recommendation or endorsement.
Unfortunately, an upgrade can sometimes go awry, causing your entire music library to disappear.
Realize that if your music is missing, it doesn't mean that your collection has vanished into thin air.
Each library has a date appended to it, for when it was added to the folder.Apple Discussions poster szadkowski: "I just installed i Tunes 8 and noticed that I'm now missing 5 GIGS of my music. It's' not in the trash, or in the i Tunes directory folder.It's even deleted purchased albums." This problem can come from two primary issues, one being a corrupt i Tunes library file, and the other being broken links in the i Tunes library from music not being kept in one location.Make the i Tunes window smaller so you can see a good portion of your desktop. Locate your "C:" drive and then drag and drop it into i Tunes.This will force i Tunes to search your hard drive for any content that it can import.