Windows 7 Boot Camp Partition Won't Defrag

Hi folks, I recently installed Windows 7 64-bit via Boot Camp on my Mid 2011 27 inch iMac so I can boot into it for gaming.

I am having issues trying to defrag though. I have tried using the standard Windows 7 defragger, which says the drive is 21% fragmented, but when I run it, it starts to defrag but then just stops and shows 21% again.

I have also tried third-party defragging programs like Defraggler and it pretty much does the same thing.

I set my Windows 7 partition in Boot Camp to be about 350 GB. I have installed Windows 7 before via Boot Camp on other Macs in the past and haven't had this issue.

Anyone know of any solutions? Any help would be much appreciated.

I have already ran a checkdisk and scandisk for errors etc.

I'm not sure what's happening but.....

I'm thinking your BC partition is nowhere near 21% fragmented. I've run Windows for years from version 3.0 up to Win 7 and have never seen a Win or DOS partition that fragmented.

I've used both the built in Win 7 defrag program and also the free Defraggler program and never had a problem with either.

Try booting your iMac with your original SL DVD and run Disk Utility from the DVD. Verify the hard drive and repair errors if any are found. That's about all I can suggest for now.

I had the same problem and tried this:
Reboot back into OSX, run disk utility and click on Verify Permissions for your Win7 partition.