@skintea Well, then move your entire The Sims 4 folder to your desktop. Do not delete it! Start the game. The start will take slightly longer because the game will create new folders and fresh files for you.
Start the game to make sure it works. This will be like starting the game for the very first time, and you will have no saves or mods.
Start a new game and play a bit to make sure everything works as supposed. If it does, then and only then you can start adding back stuff, but only a little at a time with testing the game in between restarts. If you're afraid to mess up your old saves, just place back copies of them and keep the original files safe.
Preferably, you should also redownload your CC because it may have been updated since you downloaded them the first time.
