Has this ever happened to you?
You have a “friend” who frantically knocks on your door at 2 a.m. in the morning. Upon opening the door, you see them holding their computer with a desperate expression. This can only mean one thing: your friend is having computer problems. In this case, they went and forgot their Windows logon password. Now you could always give the standard angry computer nerd response and say, “Reformat. It’s the only way,” and then laugh yourself back to sleep; however, there’s a classier solution that will leave your friendship intact and is pretty easy to boot. Believe it or not, you can change or remove the password on any Windows XP, Vista, or 7 machine with a program called the Offline NT Password and Registry Editor.
Basically, the way the program works is by accessing the registry to change the password. On a Windows machine, user passwords are stored in binary format in a file called “sam” at DRIVELETTER\Windows\system32\config. This program is able to decode the password and either modify or change it. This software is open source, and the source code is available right on the program’s website.
One warning before continuing: if the computer with the forgotten password contains EFS encrypted files, changing the password will make those files unreadable unless the old password is remembered. The most likely candidate for having encrypted files is a corporate system, but be careful and remember to ask first.
To use the program, simply download it and burn it to a CD as per the instructions on the website. Then you’ll run it just like a Linux bootdisk – once the program launches, navigate your way to the password changing function and change the password on the account you’re working on.
Be sure to read the FAQ on the website before attempting to use the program. Remember, you’re messing with the registry, so there’s always some degree of risk involved. I’ve used this program on a number of computer and never had a problem, though. It’s certainly a much easier and more elegant solution than reformatting a computer.
Remember, this is a tool. Please don’t use this for evil purposes – unless your roommate formally challenges you to hack his computer, that is. 😉