I defragged my C drive, rebooted, opened it back up, hit analyze, and it says it needs to be defragged. so,t hen i tried using Norton's speed disk. i ran that, rebooted, then hit analyze in defrag. it says i need to defrag, and norton system doctor says i am 56% defragged. this is a fairly new machine, with XP SP1. anyone have any ideas what could be causing this and how to fix it?