Difference in what you're told by the manufacturer. IE- 1,000 bytes or by system bytes at 1,024 bytes.

Tune-up Utilities 2007 is my choice of diagnostics Richard, it works for me, although you can try something aggressive like Norton's Disk Doctor, but you'll have to purchase them.

Sounds like you've lost some sectors within some clusters and you want your space recovered.

Did you check your sectors, file allocation and boot sector integrity with scandisk? If you did, do you have lost sectors? That would be the first thing to check. Make sure you have everything running in the background on your system closed before scanning.

I also suggest you not to check “automatically fix file system errors” and “scan and attempt recovery of bad sectors” on the first pass. You want to see if you can get a clean scan on the first pass and checking these aggressive features will cause your initial verification to be lengthy.

Your last resort is to unconditionally format the drive providing you can't recover the space with utilities, meaning back-up everything you want to and can keep.

Drives go bad, quickly, unexpectedly and always painfully. They can come from the manufacturer with up to 9 bad clusters and is deemed acceptable for sale.

Guys like us have to always prepare for disaster.

Good luck my friend.

Cp

I'm doing a defragmation on it right now I'll check for bad sectors next. It's still a butload of free space but I'd sure like to know what happened to rest..Thanks guys...  

try this to see where the files are...
WWW Link

If you are trying to figure where your hard-drive space has gone, or if you want to visually see how much space a file, folder or directory is taking up. You can visually see how much space the system files take or all the jpeg's or icon files or any particular file.

A program called Windirstat is one of the best hard drive utilities you could ever use.
Windirstat

Here is a screenshot of my c:\drive and as you can see the section are broken down into directories and then files. You can see one the left side my page file is 2.3GB and is shown as one of the large red squares towards the right side of the map and my next largest file is my hiberfil.sys file which is another 2.0GB which shows next to the page file on the map. The 2 large green squares are system volume info files. So as you can see, it’s a great utility for locating and managing hard drive space.

I forgot to add that you should be concerned, that's a lot of lost space.

Let us know how it goes.

Is this a new drive or one that you have had for a while? Could for some reason a program for backing up files have had it setting changed? Just guessing and throwing out some stuff here. You would hate to think that all of a sudden a third of your HDD came up with bad sectors.

Rich, Like CP I use TuneUp 2007 Utilities. If your defrag does not give you the answer try the free 30 day trials of TuneUp and PerfectDisk - they are both the full versions of the product - and between them they should sort you out.   

Hey Goo!

I'm trying Windirstat on for size right now. That's pretty hot, lots of info and it's free!

Thanks for sharing this.

Cp

  

how old is it?
did you buy it new or eBay?
do you have more then one partition?

Philly0381-- very new I just got new computer a week ago or so. I don't think there are any other partitions at least I didn't make any..Been defragmenting about 2/12 hours, is that normal?
Thanks much everyone..  I'll try and keep you updated.. When I first got it I think it was around 230 or so gb's free. Since then I've added some programs--bryce, photoshop,vue, 3d max. windowblinds, iconpackager,cursorxp,desktopx and a few other things.But I don't think they add up to 50gb's. Somethings up I hope I find out what it is..  

Gremlins

Could be...

Richard right click on your c drive and choose properties. Click on Disk Cleanup and check all the boxes. When I got my computer I had about 25gb of junk on it.

or

If you went from XP to Vista there is a folder called Old files(?) when you click on the c drive. That holds about 90gb.

Was 186 gb's an hour or so ago now it's at 180gb's...