Backing up the Sims 4 folder from the documents folder to say the desktop does not delete the Sims 4 folder or saved games. It just copies or moves it to a different spot on your computer.
Where your Sims 4 folder is (Saves, mods, Sims, Lots)
C:\Users\Username\Documents\Electronic Arts\The Sims 4
To save this folder to the desktop - right-click on the Sims 4 folder, Copy or Cut and Paste it to the desktop. This will save a copy of the Sims 4 folder to your desktop. You can then find the folder with a similar path as below:
C:\Users\Username\Desktop\The Sims 4
Launch the game, and it will create a new Sims 4 folder.
Here are the Files and Folders To Add Back In from the Sims 4 folder on the desktop:
http://www.carls-sims-4-guide.com/forum/index.php?topic=29292.msg401669#post_FF2ABNindigo mentioned to take out your mods folder. This is fairly easy to do. For testing purposes, you can right-click on the mods folder and select Cut and paste that to the desktop.
When moving the mods folder to the desktop, it is also a good idea to delete the game cache as well as the localthumbcache.package from your Sims 4 folder. [C:\Users\Username\Documents\Electronic Arts\The Sims 4]
This helps troubleshoot gameplay issues, a new localthumbcache.package will be made when you start playing again. This file is okay to delete.
Delete Game Cache Files (What and How-To)
https://www.carls-sims-4-guide.com/forum/index.php?topic=29288.msg401662#msg401662How do you repair? I've tried to look for the option a few times, all I see is a help article telling me to back up and delete the Sims 4 document folder. Ok, that deletes all my save games, but what about repairing?