I'm having a problem with my laptop (one of the 3 of 5 computers I have authorized to play my iTunes purchases). I am going to take it in to Best Buy for service, and before I did that I wanted to deauthorize this machine so my music can't be ripped while it's there, and in case they had to wipe Windows (I didn't want to waste an authorization).
When I deauthorize the computer, some of my purchases stop playing and require me to reauthorize, but some other things I bought still play, despite me deauthorizing the computer.
Why?!?