I have been playing deluxe edition Sims - happily for 5 months. I added expansion pack House Party - followed instructions carefully... It worked yesterday and today the game wont load. It says that it needs to install the add on (already done) I have tried to no avail - can anyone help please? I'm using Windows Vista and have closed all background progs. I have tried loading game from C drive and uninstall the add on house party (unable to uninstall) Help me pls.