I am using build Parallels 3.0 latest build 4128. My dad, on his pc, was haing an issue regarding dskchk with disckeeper. I decided to fire up Parallels and run the system defragmenter in XP and it told me I needed to defragment my disk. I have just installed Parallels 3.0, upgraded from build 3188, which I did before really doing anything other than installing it, because I had just bought it. I have installed a few apps, but have not run them yet. So, my question is why would I need to run the defragmenter? I have less than an hour of time on this because I have been busy with other stuff. I can run my Windows system for months writing and deleting files without needing to defrag. The second question is, should I run the defrag program now? I have seen at least one thread on corrupted hdd image file. I am a little nervous to run this, if it is going to screw up my hdd file. Thanks.