If a song used to appear in iTunes but doesn’t now, it may be because the iTunes Library file was moved, or the song was moved from the iTunes folder. To make your songs appear in the iTunes window again, try the following in this order:

Locate your iTunes folder (by default in your PC’s Music folder), then drag it to the iTunes window. You see the songs in your library again. If the iTunes Library file was included, you also see your original playlists.

If that doesn’t work, your songs may be elsewhere on your hard disk. Go to Start > Search, then search for a song by title or artist. Drag songs (or folders containing songs) to the iTunes window to add the songs to iTunes again.

If you don’t find songs by searching, check the Recycle Bin.

Or, if your library is on an external drive, make sure the drive is connected to your computer before opening iTunes. (Or, if it’s on a network, connect to the network first.)

If files have mysteriously disappeared, run a full scan of your computer with up-to-date antivirus software.

If you delete the iTunes Library file, your songs will no longer appear in your library even though the song files are still in the iTunes folder.