Just, yesterday, I played with different cpu cooling programs and completely destroyed mbr, and may be the master file table (MFT) also. First winxp systed partition was fat32 and it simply disappeared from the hd. Neither dos, nor knoppix cfdisk could see this partition. Everything says: no partition, or no data on this partition. It looked like as the partition and all data were completely lost, but of course, data were still there on the hd. Winxp recovery consoler could not help also; I tried bootcfg, fixboot, and fixmbr without any success.

What I did? I started a new winxp installation on other partition (or you can make installation to the same partition, but without formatting and to different folder keepeng old data intact; let say to c:\winxp instead of c:\windows. Next, you can add to c:\boot.ini line for both windows and boot to any of these win, or simply delete the latest. During this procedure winxp checked all disk and restored MFT which is duplicated by winxp in many places, but dos or Linux read only one located at the partition beginning. Now I have my first partition and all data back (to tell the trust I can’t boot from this partition so far, and have not found jet how to fix this. But it’s not a problem, I boot from other partition).

Hope may help.
Best, Alex