About a year ago I noticed a problem where Windows was reporting incorrect available space on a large HDD (120 GB). By this I mean if I click on the drive (e.g., in Explorer) it shows for instance 20 GB remaining. However, I can’t account for all of the 100 GB stored. If I go to the right pane in Explorer and “Select All” and then right-click -> Properties Windows returns a message 35 GB used. I have the options selected to “show all files” so this isn’t a hidden file problem.

Initially, I assumed that this was a HDD problem so I contacted the manufacturer (Maxtor). They had me run some diagnostic software that indicated that the drive was operating normally. I wound up reformatting the drive and it worked okay for a while, then little-by-little began reporting less and less free space (incorrectly). Convinced that it was a HDD problem, I purchased a second 120GB HDD (Western Digital) and installed it as an additional drive. Darned if the WD HDD didn’t begin having the same problem. I then assumed that the problem was with my OS, so I reinstalled W2K. That didn’t help. Finally, in my frustration, I purchased XP Pro and that’s what I’m now using. The problem is still occurring. I have enough storage space that I occasionally just dump all files onto one drive or the other. The errant drive will still show like 30 GB space used even though there are no files on the drive. I’ll reformat the drive to get all of the space back. Of course I’ve used ScanDisk, CHKDSK, Norton Disk Doctor, and other utilities at my disposal - no luck.

I have a smaller 30GB HDD where my OS resides and it never has presented the problem. The two 120GB drives are used for large video files, sometimes in the 10-30 GB size range (AVI files). All 3 drives are NTFS.

So, I’ve eliminated the HDD as the problem (2 brands) and it’s not the OS unless it’s a problem with W2K and XP. What else should I check? Could it be a motherboard or IDE controller problem?

If anyone else has seen this problem or has a clue as to what’s going on, I’d appreciate your thoughts.