Circa 700GB of my Hard Drive lost!

Hi guys

I'm rather puzzled and a bit concerned as I seem to have lost a huge amount of hard drive space!

My C: drive is a Samsung SSD 840 EVO 1TB ATA Device. When I last noticed (about a week ago) the disk usage it was in the region of 320Gig, all my data files are stored on a separate drive.

Today, I noticed that I only had circa 34Gig free!!!

I've researched the issue on various sites and checked common suggestions like:

• System Restore points - I disabled system protection and previous restore points were erased.
• Pagefile - my Pagefile.sys is aprox 16Gb insize and managed automatically.
• Carried out a Disk Cleanup

I downloaded and ran WinDirStat and these are the results:
931.4 GB C:\
763.2 GB C:<Unknown>
42.6 GB C:\Users
34.7 GB C:<Free Space>
27.8 GB C:\<Files>
24.3 GB C:\Windows
17.2 GB C:\Program Files (x86)
7.6 GB C:\ProgramData
6.8 GB C:\Program Files
4.3 GB C:\Onyx Ten
1.3 GB C:\Onyx10
686.3 MB C:\MSOCache
220.0 MB C:\Samples - EmbroideryStudio e3.0
195.3 MB C:\Jobs
164.4 MB C:\Recovery
138.0 MB C:\epson
30.8 MB C:\Temp
22.6 MB C:\eCut
10.3 MB C:\WilcomClipArt
1.2 MB C:\Intel
821.2 KB C:\_rpcs
219.3 KB C:\$Recycle.Bin
0 C:\DiskD
0 C:\Documents and Settings
0 C:\PerfLogs
0 C:\SUPERDelete
0 C:\System Volume Information

Disk usage report generated by WinDirStat.

The 2nd entry in the list '763.2 GB C:<Unknown>' is what I think I should have free.

I've completed a chkdsk without any issues flagged.


Last week I added a Thecus 5550 NAS and used a sync program called Alway Sync Pro to sync my My Documents folder, about 350Gig in total to my NAS. The My Documents folder does not reside on my C: drive. While carrying out this process the program displayed a Pagefile error and the sync failed. I was advised to increase the size of the pagefile which I did and completed a sync. I've since reset the Pagefile to be managed automatically.

I think that during running the sync on one occasion my computer BSOD! This might have happened after I'd manually set the Pagefile to a much bigger size and I wonder whether this is being reported as the 763.2 GB C:<Unknown>. Other than that, I have no idea what is gobbling up 763Gigs!

I'm really stuck and any help appreciated.

John

Thanks for the reply. I was of the same thought but couldn't find any folders/files occupying anywhere near the space I'd lost.

I downloaded a few utilities to find the folders/files and TreeSize Professional found what I was looking for. Within the Windows folder was another folder CSC, within this folder were several copies of the files I'd transferred to my Thecus NAS. After doing a couple of Google searches I discovered that a setting 'make offline files available' (or similar) was ON. This is why there was a copy (more than one) of the files I'd transferred to the NAS taking up a huge amount of space.

Microsoft provide a registry edit automatic script that corrected the problem and after a re-boot I'd recovered my 700+ Gig of space.

Thanks for the suggestion.

Cheers

John