Windows XP is screwing up on me! I thought that I had noticed this problem before, where deleted files wouldnt recover the space it used to take up, but usually it was with relatively small files and I never looked into it. But recently, after deleting a huge 800mb avi file (the avi file, if viewed by a text viewer, had no text and no data, like a dummy file if anyone knows what I mean), the hard drive space did not recover any of the 800mb. In other words, before deleting the file I had 3.2gb of space left, yet after, I had 3.2gb of space left! I have no viruses, no bad sectors, and no "foreign" programs that I am unaware of. I have tried rebooting the computer, as well as searching my hard drives for any 800MB size files. Please help me with this. If you need any clarification please ask!

Did you open and empty the Recycle Bin ? The files will still be listed as used space until you do. Do you have Norton Utilities installed, with the Protected Storage Bin feature ? It hangs on to files for a while. Finally, you may want to go to the Command prompt, type in 'sfc/scannow', with your Win XP cd in the drive. It will look for missing or corrupted system files, and replace them. Takes about 20 minutes. Something may be missing that causes the hard disk space problem.

reboot after emptying the recycle bin.

It looks like an XP bug to me. I deleted 8 gig of avi files, and emptyed the recycle bin and I dont have norton installed. I turned my web cam back on and after about 30 200meg files the system shut down the process with a message in event viewer saying that I had less than 200 meg on the drive. I tried to run defrag but got a message that defrag wants 15% free space on the drive inorder to run. Fortuantely I use this as a scratch drive so I was able to just format the drive. Theres deffinetly something buggy going on.

Well, just a follow up for anyone interested. I used QuickWiper to erase the unused portions of my hard drive, and it was able to weed out the mysteriously hidden files. Other free space wipers didnt work for me, including Norton's CleanSweep.