How to recover unknown password in Windows XP?

Ophcrack LiveCD
Windows Password Cracker

You can always crack the password as others have mentioned.


If you just need to get in to access some stuff temporarily... one method I used a long time ago... is booting to the recovery console... and then copying these files to a temporary location...

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copy c:\windows\system32\config\system c:\windows\tmp\system.bak
copy c:\windows\system32\config\software c:\windows\tmp\software.bak
copy c:\windows\system32\config\sam c:\windows\tmp\sam.bak
copy c:\windows\system32\config\security c:\windows\tmp\security.bak
copy c:\windows\system32\config\default c:\windows\tmp\default.bak
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Then I used a password reset tool to change the account password. Then I restarted, logged in with the new password and perform what I needed to get done. Once I was done, I restarted into the recovery console again and I restored the old password by doing the following...
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delete c:\windows\system32\config\system
delete c:\windows\system32\config\software
delete c:\windows\system32\config\sam
delete c:\windows\system32\config\security
delete c:\windows\system32\config\default

copy c:\windows\tmp\system.bak c:\windows\system32\config\system
copy c:\windows\tmp\software.bak c:\windows\system32\config\software
copy c:\windows\tmp\sam.bak c:\windows\system32\config\sam
copy c:\windows\tmp\security.bak c:\windows\system32\config\security
copy c:\windows\tmp\default.bak c:\windows\system32\config\default

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