Missing diskspace

[kartak.mahino]

I'm not sure if this is a Thinkpad problem or not. My hardware Thinpad Z61m, 120GB (effective 107GB) hard drive. Windows XP SP2, 1GB RAM.

Till about 2-3 weeks back I had 50+ GB free space. I must have transferred some pictures and stuff not exceeding 3 GB.

2 days back I noticed that the space is down to 21GB. The TreeSize (Free) is showing C: has 54XXXMB and at the bottom showing free space 22XXX MB. The C: properties shows:
Used 85.5, Free 21.7, Cap: 107. Chkdsk is showing something similar.
Differences between Chkdsk & Tree Size.
C - 183821 files + 17930 indexes.
T - 178234 objects.

I checked the usual suspects:
o R&R has no backups ( I deleted them all couple of months back)
o R&R is not doing any backups, since most of the time it is scheduled my computer is not on.
o Did defragment - no success
o Did chkdsk /f - Event viewer showing (cleaning up minor inconsistencies, unused index entries, unused security descp)
o Checked system restore - It is at 12% (so 13XXXMB, not that it uses all)
o Took ownership of System Volume Information - size 2GB.
o (Edit:) Treesize count includes hiberfil.sys and pagefile.sys

Any idea where my 30 odd GB is disappearing and how can I recover it?
How TS and chkdsk is showing a difference of nearly 23000 objects?

Thanks for your responses in advance.

K
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