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I've got an Issue with a Windows XP SP3 machine that seems to be mis-reporting the drive space in use.

The machine has a 74.4 GB drive formatted in NTFS and using Treesize Free, is only showing as 28GB (27.somethingorotherGB) total data.

Naturally suspecting System Restore, that has been disabled, and I've checked that the system volume information isn't still full, by giving myself read permissions on the System Volume Information folder... which now shows as 0 bytes.

I've also disabled Offline Files, as there is a fairly large cache for that, and I needed to rule it out.

What would be the next steps on this one, to find out where all the space is in use, as I'm fairly sure it's not a 1024bytes issue ;)

Many Thanks,


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migrated from Oct 18 '10 at 13:01

This question came from our site for system and network administrators.

May want to check the pagefile.sys and hiberfil.sys located at C:\ as well. – qroberts Oct 18 '10 at 14:22
"seems to be mis-reporting the drive space in use." You need to explain better how you arrived at this assumption. When you say "Only showing 28GB", what are you comparing this to? – Moab Oct 18 '10 at 17:08
I'd bet it's a combination of the hibernation file and VSS, but people have already said both. +1's all around. You really could give some more detail though...what free space are you EXPECTING to see and how much do you ACTUALLY see? – Shinrai Oct 18 '10 at 21:12

Try running vssadmin list shadowstorage - I've had issues where I've lost about 30GB to VSS before..

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If the disk space is truly unaccounted for, try running a disk error check from the Windows disk properties dialogue box, tools tab.

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