Files under system32\config as generally registry hives (where the registry lives)
system32\config\system and system32\config\software can be easily damaged or corrupted in case of power drop in the system.
Note that unlike other system files do not think about restoring them using the expand command from the windows XP recovery console, these file contain YOUR registry and you don’t want them replaced with the stock XP empty registry.
2 Ways to solve this:
1. while the system is booting and before it displays the error press and hold F8 then select “Last good configuration” if the system boots OK then you should party can consider your self lucky.
If not go to step 2.
You must insert your windows XP installation CD and then boot from it (check your bios settings for that) on the first screen where you choose what to do press ‘r’ wait until it ask you what windows installation you want:
select the number of the corrupted installation by pressing it’s number for example 1 and ENTER
if you have a password for the Administrator account you should know it and write it when asked to
if every thing is ok you should see a prompt like this
now write the following at the prompt and just change C: to your windows directory
copy system c:\windows\bak\system.bak
copy system c:\windows\system32\config\system
ok now stop, don’t write this just stop ! 🙂
your system will reboot and it should work just fine but some registry keys way get lost because we actually restored a backup of the registry and its age depends on your system.