Foobar2000:FAQ
A rather extensive FAQ is available at the SH/SC Wiki.
Q: Album list shows dead entries after a restart, even though I used "Remove dead entries" before. Why is that?
A: The files are probably still contained in one of your playlists or in the history (only if you are using an older version of foo_history). Use "Playlist/Remove dead entries" from the main menu on all your playlists, or remove the dead entries manually. As long as the files are on a playlist, they will be in the database and thus will show up in album list.