Regain your PC's administrator rights, even if you don't have the password

Your Windows PC has at least one administrator-level account. If you can't access that account, you've got a problem--you can't install or uninstall programs, or change certain settings.

I'll tell you a way to gain this access,  but first, ask yourself if you really should be doing this. If it's unquestionably your computer and you've forgotten your password (or if the previous owner failed to give it to you), you have every right acquire or change the password. But if it's a company computer and the IT department wants to keep full administrator control to itself, this is a good way to get fired. And if it's someone else's computer, it's a good way to get arrested.

You can access the password through the free Trinity Rescue Kit. It hasn't been updated in two years, but it still works like a champ.

Before we get into details, some warnings:

1. Since it can change or remove the password, but not reveal the existing one, Trinity won't let you secretly gain control of the PC. The rightful administrator will find out that you've been tampering with it. 
2. If there are EFS-encrypted files in the administrator's libraries, these files will become inaccessible. Decryption will only be possible if someone backed up the credentials ahead of time.
3. I successfully tested this technique in Windows 7, and have every reason to believe that it will work in XP and Vista. It will not work in Windows 8.

Trinity downloads as an .iso file, which you can burn to a bootable CD. You can also use the Universal USB Installer to create a bootable flash drive. (If you don't know what I'm talking about, see Boot discs explained: An overview of booting your PC from something other than your hard drive.)

When you boot Trinity, you'll find yourself in an ugly, text-based environment. But not a difficult one. From the initial menu, selectWindows password resetting.

At the next prompt, select Winpass with prompt for username first, then enter the login name for the administrator account.

Most of the questions you'll be asked are easy to answer. When you get to the User Edit Menu prompt, select the first option, Clear (blank) user password. That will allow you to boot into the administrator account without entering a password.

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