<unknown> files and folders

I wonder if you have any ideas for me on this odd problem I have. My ASUS ZenBook is showing its 250gb SSD as having 100gb + in use when its just the OS, programs, a few emails and XAMPP (which I use for writing phpBB forum extensions) there is no data stored on the machine other than that, so I have always thought 100gb was very high. All music, photos and the like is on my NAS or the 'real' PC. I have finally done some looking around and found WinDirStat which shows that I have almost exactly 50% of the used disk showing as <unknown> files/folders. They do not show in the C drive even with hidden files and folders shown.

Any idea how I can remove them? The WinDirStat delete function is greyed out when I right click on <unknown> and I have no idea how to search for them on the disk. I have tried chkdsk /f C: (I found that on line in an answer to a similar question) with no luck.

I have booted in Hirens which showed several unknown recycle bin entries that were not previously showing in the recycle bin. Deleting those has released about 10gb.

Have you any ideas (other than flatten the disk and re install)

I have attached screenshots showing the discrepancy. W10 1803 build

Many thanks

Disk.jpg

WinDirStat.jpg

It's possible that these are Shadow Volume Copies, which are related to System Restore points.

Personally unless you're short of disk space I'd leave them alone, but if you absolutely must remove them, then the easiest way is to use Window's Disk Clean-Up utility.

• Launch Disk Clean-Up and allow it to finish its initial scan.
• Click on Clean up System Files and select your C: drive (or whichever your system drive designation is), then wait for the "new" scan to complete.
• Click on the More Options tab
  
  • Under the System Restore and Shadow Copies section, click on Clean Up
  • Click OK and wait for the cleanup to complete (this can often take a long time).

Thanks for that Gary, but I had already tried it (I use Acronis for my backups, so restore is disabled anyway)

OK, can't think of anything else just now, but I'll ask around and/or have another think, and see if I can come up with another idea.

Cheers Gary. Its not important, just annoying and confusing.