This is probably becuase you installed House Party
AFTER the more recent expansion packs. You see, there is a special order that you MUST install them in if you want this to work. Here is the order: The Sims (original version)/Deluxe Edition, Livin' Large, House Party, Hot Date, Vacation, Unleashed, Superstar, Makin' Magic. I know you don't have some of these expansion packs, but that is the order that they all need. If you don't have one of the packs, just skip over it and go to the next one that you have. Sadly, the only way to fix the issue you have to to uninstall the game, and install the packs as I listed above. If you want to keep your families, I suggest teleporting them to the Sims website. You can download them once you get reinstalled. If you have any further questions, let me know
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