Some of that missing space could be accounted for via the swap file, although 13GB is probably a little on the outlandishly large side.
Have you run a virus scan and a spyware scan lately? Further, when was the last time you went to the Windows Update site? Because it may be that someone has compromised your system and turned it into their own private storage facility.
Also, are you sure a program such as Kazaa or some other P2P program isn't downloading things to the partition in question instead of another like you thought it was?
First off, I'm running a custom computer with Windows XP pro, an athlon XP 2200 with an MSI K7N2G series mainboard (MS-6570 ATX version), 512 megs of ram, an 80 gig hard drive with 4 partitions (c, d, e, and g), and optical and floppy drives.
My main partition (my 'c' drive) in my hard drive is running very low on storage space (only about 50 megs left, out of 20 gigs).
When I check the "properties" of my 'c' drive under 'my computer', and under the partition manager screen, it says that I only have about 50 megs of storage left (about 19.95 gigs of storage used).
The problem is that out of the 20 gigs I'm suppose to have on that partition, I really only have about 6.63 gigs of stuff on there. when I go into my 'c' drive and 'select all,' then check to see the properties of everything that I have selected, it only shows that I only have 6.63 gigs of data (mostly Windows stuff and some program files and desktop stuff), which should be about right since I store most everything else in my other partitions. I tried to check if maybe I have hidden files in there and just can't access them or what, but I can't tell. It's as if I just have a block of 13 gigs of invisible, inaccessable data stored in my drive. I don't get it.
I've tried to delete unnecessary programs, used the disk cleaner tool to compress and delete temp files and tried defragmenting but I still can't seem to free up any space. About a week ago, I freed up about a gig of storage space, but now that has filled up too, without me installing any new programs or anything that I'm aware of. I also turned off my system restore function to try to free up space, but that didn't help much either. Now I can't do anything cause my main system drive is too full. But like I said, the problem is that I should only have about 6-7 gigs of stuff in there.
There's something else. About 6 months ago I tried to delete my entire hard drive (3 partitions total) because my computer was too clustered and unorganized (I know, wasn't the best idea I've had). I was able to delete 2 of the partitions but not my main system drive. so I just tried to delete as much as I could from my main drive and then tried to install the operating system on top of it (same OS). It seemed to work because after the OS install, I just had a basic computer with no other programs on it but Windows. Then I created 3 more partitions with the rest of the hard disk space. Everything seemed to work out fine. But what I noticed was that my main system drive already had about 14 or so gigs of stuff on it (roughly what I had left over from the previous setup plus the new OS install), even though I couldn't locate any of it anywhere. It almost seemed as if it just loaded the new OS into the old partition but wouldn't allow me any access to the old data. I really don't know to be honest, just speculation.
My other partitions are fine, with plenty of storage space still. It's just my system drive that is filling up.
Any idea as to what happened and how i can free up some space? I know this is kind of a multi-part problem, but if anyone could help me out, I would greatly appreciate it. Thanx.

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