Scandisk in WinXP is known as "Error Checking" and you reach it the same way you reached your defrag program. If you have a cable/broadband connection on your computer, when you do an error check you may receive a message that it can't be done right now, other things are using the system, do you want to do it the next time you restart. Choose yes and then restart. Just let the computer do it's thing. It will do a "scandisk" (my DOS background is showing, since I still call it a scandisk). After your computer has finished and is re-booted, once again try defragging. If it still won't defrag, then trying Lori's method is a good idea or you can download a defragging program (try
www.tucows.com for some freeware/shareware options). Windows native defrag program is not the best but if it works, it is adequate.