@harperelyzabeth
We have seen this error in the past with broken default replacement eyes. Have a look at this AHQ topic for more information.
You might also try the following, to see whether your game works without mods:
- Move your entire mods folder somewhere safe (there's no need to delete it!) such as a folder on your desktop so you can easily find them again.
- Make sure to delete your localthumbcache.package file.
- Once done, start up your game and test to see if the error still appears.
Your game will probably work flawless without mods. If that's the case you have to go through your mods and find the culprit. The 50/50 search might be a good method for this task to get a result in a reasonable time.
Attention:
All modded content will disappear from the game if you remove it, so if sims are wearing CC it will vanish while you're testing.
Because of this it's really important that you do not save the game while testing.
That way your CC will still be there when you bring your mods back into your game.