@AbC1428a8036907 The more CC you have, the longer loading the game will take. And if it won't open at all after you add new CC, it almost always means you have CC that's not compatible with the current version of the game, and you need to figure out which CC that is:
- Exit Sims 4 then drag your Mods folder to your desktop.
- Then delete the file called localthumbcache from Documents > Electronic Arts > The Sims 4.
- If you think you might accidentally forget to exit without saving after testing, copy your Saves folder to your desktop too, to back it up.
- Now open Sims 4 and see if you still have the problem.
If you don't, you can start the process of figuring out what from your Mods folder was causing it by using the 50-50 method (the steps are in that link) to isolate the broken files. This is also a good time to find duplicate files and to delete CC you haven't used in a very long time. This will help speed up your load times.
Another way to speed up game-start time (once you've got it opening again) is to go to Options > Other and tell it not to show you the list of mods/CC on startup.