Tracks not showing up

Some albums show up in playlists in the library with artwork and all album information showing but when opened they show and play no tracks. Checked with the source files and they are all there sitting happily in the album folder and nothing has changed in the location or naming of anything.

Is there a reason why this happens and is there a way to force the library to find them again? I have resync’d in the Library preferences but no happy outcome. Not sure what else I can do without losing my datafile and the hours of work therein.

The missing files I am looking at just now are .aiff, ripped from a CD and, as I recall, have played before without a problem; these are old files.

Try removing that folder out of your music hard disc, let A+ sync and see them disappear from your database, close A+. Reopen it and put them back where they were.