Let us assume that you have a situation WinXP Pro or Home, Will not boot into normal mode, safe mode or safe mode command prompt. Last known good configuration fails. Repair install fails. Now the OS needs to be wiped clean and reloaded.
How do you get the CD key before wiping it out?
Here is the simple solution hope this works for you too
ok first boot with a bartpe cd Download bart PE iso from here with a dos reg editor on it open the windows regerstry and export the key HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion save it as a reg file on a cd if you have the nero plug in for bartpe or any usb drive it wont fit on a floppy it is too big
next go to a working xp computer open regedit and export the key HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion to back it up then put the cd or usb drive in to the working computer and import the reg key then use keyfinder or any prog to see the key right it down then import the backup reg key back in to the working computer do not reboot or turn off the working computer with out puting the old key back
1. Created a Bart PE iso, nothing extra added, just used defaults.Download bart PE iso from here
2. Booted dead system from PE CD.
3. Downloaded LoadHive from here and put it on a floppy.
4. Ran it from the floppy in PE, loaded C:\WINDOWS\System32\Config\software … it mounted as SOFTWARE_00.
5. Ran regedit, found the SOFTWARE_00 subkey and navigated to CurrentVerion, exported that subkey to the floppy.
6. I moved to a working XP machine, backed up my DigitalProductId key. I edited the reg file from the floppy to only contain the DigitalProductId key.
7. Merge the DigitalProductId key from the floppy, ran Keyfinder (Magic Jellybean Software) and it pulled the key !
8. Merge the backup I made and ran it again, and sure enough it had my original key.