It's installed by default in Windows operating systems and takes control of your Documents folder by default, locking any files in it until they're backed up. One of the single, most common causes, is Mircosoft's Onedrive. It might be a bad mod (we hope not, we check them all) or that one mod is not compatible with another, or perhaps your computer glitched during the install of a mod or the CC Manager itself, or you experienced a disk failure.
Modding any game is wonderful until something goes wrong.
