You'll find the following files in the snapshot folder:
_REGISTRY_MACHINE_SOFTWARE
_REGISTRY_MACHINE_SAM
_REGISTRY_MACHINE_SYSTEM
_REGISTRY_MACHINE_SECURITY
_REGISTRY_USER_DEFAULT
Copy these files to the Windows\tmp folder that you created earlier. Rename the files as follows:
Rename _REGISTRY_MACHINE
_ SOFTWARE as SOFTWARE
Rename _REGISTRY_MACHINE_
SAM as SAM
Rename _REGISTRY_MACHINE_
SYSTEM as SYSTEM
Rename _REGISTRY_MACHINE_
SECURITY as SECURITY
Rename _REGISTRY_USER
_ DEFAULT as DEFAULT.
From within the Recovery Console, open a command line, and type the following lines, pressing Enter after each line:
del c:\windows\system32\config software
del c:\windows\system32\config\sam
del c:\windows\system32\config system
del c:\windows\system32\config security
del c:\windows\system32\config default
copy c:\windows\tmp\software
c:\windows\system32\config\software
copy c:\windows\tmp\sam
c:\windows\system32\config\sam
copy c:\windows\tmp\system
c:\windows\system32\config\system
copy c:\windows\tmp\security
c:\windows\system32\config\security
copy c:\windows\tmp\default
c:\windows\system32\config\default
Type exit at the command line to quit the Recovery Console, and the system will reboot. Assuming all repair hives are correct, XP should boot normally and return to a state similar to the one before the problem occurred.