Unable to rename sims 3 folder?

My game is crashing on startup for seemingly no reason, so i decided to try and factory reset by renaming my sims 3 folder and having the game generate a new one. However, it says its unable to be renamed because the folder or a file in it is open in another program. I've tried closing everything i have running and it still says it. Any idea on how to fix?

Restart your computer.