Large discrepancy in C drive used disk space

LMiller7 said:

Yes

The value shown for total disk space used in the disk properties is maintained by the file system and is completely accurate.

But for a variety of reasons, some quite complex, the file system does not keep track of the disk space used by individual folders. To show this in the folder properties requires a complex and potentially lengthy process. It requires examining the contents of each subfolder and each one it contains to check the file sizes. This could easily mean examining several hundred thousand file entries. There are all kinds of complications in doing this and the result is at best only an approximation.

One big problem is with folders like "System Volume Information" which contains the restore points. Typical space consumed would be at least several GB. By default even an elevated administrator account (or even the built in Administrator account) has no access to it. The fact that Windows Explorer is a part of Windows doesn't give it any special privileges. If your account has no access, it won't either. This is necessary to maintain security. That means the attempt to examine it's contents stops right at the beginning and the size of the folder is seen as zero, and reported as such.

WinDirStat has the same limitations as Windows Explorer.

if you have an image of the subject drive, say with Macrium, you can mount the image and explore the contents of the System Volume Information folder. You might also be able to see it with MiniTool Partition Manager Free by selection the drive and using Explore.

You can also run Wiztree (portable):
http://antibody-software.com/web/sof...ur-hard-drive/