I wish, I would have read this post little earlier. This has happened to my pc and windows thousands of times. Trust me, none of the tricks mentioned above work in this situation. And how it feels when you have many important files on C: and you cannot just think of removing them by formatting the C: drive, ask me!!!!
OK, do this,
1. Reboot your PC if C: drive is formatted with fat32, no ideas about ntfs because I never formatted my C: ntfs, yes, reboot your computer with one windows98se cd, always keep it guyz, trust me it always comes to our help in such times.
2. Choose the second otion of boot computer from cd rom.
3. then take 3rd option, with something like help.
4. When you see A: on the dos scree, type cls to clean the screen. And then, what I always do,
G:\smartdrv to check the status of smartdrv, of course to load things faster.
or if you're already in g: drive by typing g:
In this way, you deleted all your windows and program files, now install fresh xp without formatting your c: drive and of course, without loosing any of your important data, plus all viruses gone with windows directory.
Things to remember before, download smartdrv, deltree and scandisk from the internet, google for it and you will find it. Then always keep them in any of your other drives than c:. and one copy of 98, done,,,,,,..
You all will thank me and pray for me after doing this if fallen in such situations.