Sims 3 Worlds Won't Load

I recently downloaded all my Sims games, including the Sims 3. It previously worked with no issues but now every time I try and load a world it loads super quick, which never would happen, and it says "A serious error has occurred while loading 'worldname'. It is strongly recommended that you restart the application. Ive "repaired" it and restarted the game and it still doesn't work. I don't have any mods or cc downloaded but yet its not working at all. All my other Sims games work but not the Sims 3. I should mention I was playing yesterday and it worked perfectly fine.