Re: Sims 4 wont start with mods...
To add on to the solution, this will make it less tedious!
Within folders, organize your mods by freshly downloaded, recently downloaded, eldest downloads or something of the like.
Take your newest folder and place it into your Mods folder. Launch your game, see if it works, and save that folder as ones that work. Continue like this for each folder. Keep track of the one that doesn't work.
Take the folder(s) that doesn't work and dissect it. First, take the portion in your folder that is created by one artist (e.g. the largest amount of cc by one creator) and see if all of those items work in your game. Proceed with testing your broken folder's cc within groups of 3 - 5 (this will have it done faster).
Please take caution that mistakenly downloaded Sims 3 and Sims 2 cc will break your game and cause it to be unlaunchable.
To keep your game safe within the future, make a "Just Downloaded" CC folder and test only that folder in-game once you've finished downloading cc (this is so you won't lose faulty cc in the other files and then have to clean it out again, this become irritating.)
Good luck.