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Windows 7: Circa 700GB of my Hard Drive lost!

31 Dec 2014   #1

Windows 7 Ultimate x64
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.


My System SpecsSystem Spec
31 Dec 2014   #2

Windows 7 32 bit

Welcome to the Forums.

I suspect it is temp stuff for the sync to the NAS. Can you look at any of the files? Make sure you have folder settings to display hidden files and folders. See what they look like.
My System SpecsSystem Spec
01 Jan 2015   #3

Windows 7 Ultimate x64

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.


My System SpecsSystem Spec

01 Jan 2015   #4

Windows 7 32 bit

Glad you got it going. Those file/folder/disk analysis tools are great to have. I use WizTree freeware. It only works on NTFS but since it uses the MFT info it is lightning fast.

My System SpecsSystem Spec

 Circa 700GB of my Hard Drive lost!

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