after installing an expansion pack

Okay, so I already have the sims (base game), generations, pets and showtime installed before I started to install another expansion pack (supernatural) . But when I tried to install another expansion pack, it didn't work out very well. I did everything in the instructions on how to install it, and even did the latest fix. I did it again and again. But when I tried to play it, it wouldn't open. Like, I would just click on play, but nothing happens. What should I do?

Please re-do steps two to four from this page. It should bring you all the way up to date, and makes sure that you have the most recent fix. (So do re-download it all, and apply the patch, even if the game says you're up to date already.)