@gnarlycamiYou could move the entire mods folder to the desktop. The game will always create a new empty the same folder in its place together with the new resource.cfg file after switching on - this is more convenient.
But if you have already done it in a different way then leave it and this file has to stay.
Then follow the instructions given above - delete localthumbcache.package file - important!
And fix the game in Origin.
Origin/Library -right click on TS4 - option "Repair game"
You have to wait until Origin will fix all packs, not only the base game.
If your game after repair and without mods works, first, check if there are new updated versions of the mods and CC you are using.
Then copy from desktop your mods and CC and paste it in the new mods folder.
First, paste script mods one by one every time checking if the game is OK. Do the same with CC but if you have a lot of this, try the 50/50 method.
You have to find the culprits and delete or replace them with updated versions.