Weird HDD problem

[NineLives]

So my HDD says that it has 313gb of data via windows explorer, but upon backing up that whole drive it really only has 189gb of data per windirstat. http://img545.imageshack.us/img545/3830/wtfvs.png there is a picture.. What could be causing this?

[supaflyx3]

Hidden files maybe, I'm not sure if windows explorer takes those in to account.

[_dangtx_]

look up partitions,hidden or not

then use treesize

[frontier204]

I second supaflyx3's suggestion that it's admin access. [Edit: This looks like the case because "System Volume Information" reads as size 0.] Did you run WinDirStat as admin?

The other possibility could be errors on your drive (i.e. run chkdsk and try again), or block sizes. Notice for small files that the "size" and "size on disk" are different?
I never checked which one of the two WinDirStat uses, but if you have a lot of little files (i.e. from doing work with programming), the difference can add up to be quite large.

[ipaine]

Originally Posted by _dangtx_

then use treesize

I highly recommend Treesize. It can show you how much space is actually getting used and what is using it up. You can get a free version here: TreeSize Free - Quickly Scan Directory Sizes and Find Space Hogs
Or you can pay for the pro or personal versions.