Refreshing iTunes cover art for TV shows

Hi All,

I have a large collection of TV shows in iTunes - many of which are purchased from Apple. Since the size is over 1TB, I've moved them all to an external HDD and then reimported without copying to the iTunes media folder.

Anyway, I use a MacBook Pro for iTunes and frequently open iTunes to playback music without the external HDD connected.

Sometimes when I do this, iTunes loses the TV show cover art (doesn't seem to happen with movies, even though these are structured in the same manner on an external HDD). Even when I re-connect the external HDD, I don't see the cover art for TV shows. To restore the cover art, I need to select each file individually and open Get Info (i.e. command+I). That works, but I have way too many TV shows to go through that again.

Is there a way to cause iTunes to refresh the cover art cache from the files themselves, when the external HDD is connected?

I can't believe I am the only one having this problem...

Thanks,

Ken