You can now start to copy back things from Documents\Electronic Arts\The Sims 4_Old to the new Documents\Electronic Arts\The Sims 4 folder that was created.
First only copy (I suggest to copy so you can go back in case anything goes wrong along the way) the content of the folder Saves (these are your save games). If you are prompted if want to overwrite a save, decide if you want to keep that testing save you just made or not. If not, just overwrite if, if you want to keep it, rename the save to a different number that isn't taken.
Test just your save game with nothing else added back. If that works, you can start copying back the rest. If not, check back.
You will need the following folders
- Tray (your households and lots you have saved to library)
- accountDataDB.package (your event rewards)
- Custom Music (if you added any)
- Screenshots (if you've taken any)
- Videos (if you've taken any)
- ConfigOverride (if you made any although I recommend redoing those)
- Options(.ini) (although I recommend to just redo your settings in the game)
Now test again. If that still works, you can put back your mods. Put them back in groups and make sure they are still compatible with the game.
All other files are recreated and not needed.
