Reset Windows Password with Ubuntu Live CD

Solution 1:

You mustn't change the password with chntpw, what you can do is reset it (if you could change it that means that you can read the previous password). The correct way to use it is:

cd /media/B830C9BC30C981BC/WINDOWS/system32/config
sudo chntpw SAM SECURITY

(change B830C9BC30C981BC as appropiated)

Once in this screen you will get to answer several questions. READ CAREFULLY. Select the account you want to modify then reset the password.

1 - Clear (blank) user password
2 - Edit (set new) user password (careful with this on XP or Vista)

If reseting the password directly doesn't work, you can activate the Administrator account and from there reset your password.