Very large Reserved MFT

I was using defraggler and everything was fine. A download finished on my E Drive so I stopped defragging and moved those files onto my C drive. Rebooted and started Defraggler up again.

This time though when I hit the defrag button for my C Drive, Defraggler popped up saying that I had less than some percentage of 'real' free space left. Do I want to continue? I hit yes and its still all good.

Seems my C Drive got a large portion turned into 'Reserved MFT Space' sometime after I stopped the defrag process the first time. As you can see from my screenshot, free space is 23%, and when I moused over the purple squares Defraggler told me they are empty.

Anyone have some insight on this? Why did I suddenly get a very large Reserved MFT Space?

Edit: forgot to upload screenshot

post-34941-1264299860_thumb.jpg

I've experienced this too on Windows XP and there have been discussions here about it. At first I didn't think too much about it but have since started to believe it's not normal. What I did to fix mine was to defrag and move every file to the end of the drive, reboot and then defrag again normally moving everything back. It worked for me and the Reserved for MFT started displaying normally. I don't know if it'll work every time though.