I've been working on this one for about an hour, and haven't made any progress... When I try to purchase an album via iTunes, I get an error "Purchase of this item is no longer available. This item is being modified. Please try again later." The thing is, it comes up with anything I try to purchase. On my PC, it works fine, but I don't use my PC for music. I can't figure out what could be the problem. Any ideas???