Super User is a question and answer site for computer enthusiasts and power users. It's 100% free, no registration required.

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

I accidentally changed one parameter in Windows and it was crashed and restarted everytime I logon. I can't go with safe mode. Restoring to Known Good Configurations doesn't work too.

Unfortunately I don't have system backup. Are there any ways to recover or edit the registry file from another OS or bootable Windows PE? Which tools can I use to edit?

Many thanks!

share|improve this question

Another install of Windows or WinPE would work fine. Once it's booted, go to the command prompt and do something like this:

reg load hklm\Old_System C:\Windows\System32\Config\System
reg load hklm\Old_Software C:\Windows\System32\Config\Software

if you need your user settings:

reg load hku\Old_User C:\Users\Jack\ntuser.dat

The registries can them be edited with RegEdit, note the slightly different names (HKLM\Old_System instead of HKLM\System). When you're done, unload them like this:

reg unload hklm\Old_System
reg unload hklm\Old_Software
reg unload hku\Old-User
share|improve this answer
So simple, and yet so hard to find! Beautiful answer, thank you. – Tao Dec 2 '10 at 17:25

Chris S's answer looks like the best method. If you can't go the WinPE route then there's a tool called ntpasswd. It's a bootable CD used to recover forgotten passwords but it can also be used to edit the Windows registry.

Download the bootdisk here:

And here's a guide on how to use ntpasswd's registry editor:

share|improve this answer

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.