Deep inside the bowels of Windows Vista, there’s a secret Administrator account, and it’s different from the normal administrator account you most likely have set up on your PC. This Administrator account is not part of the Administrator group. (Confused yet? You should be.) It’s a kind of superadministrator, akin to the root account in Unix, and by default it’s turned off and hidden. (In describing this tut, i’ll always use the capital “A” for the secret Administrator account, and a lowercase “a” for a normal administrator account.)
In versions of Windows before Windows Vista, the Administrator account wasn’t hidden, and many people used it as their main or only account. This Administrator account had full rights over the computer.
In Windows Vista, Microsoft changed that. In Vista, the Administrator account is not subject to UAC, but normal administrator accounts are. So the Administrator can make any changes to the system and will see no UAC prompts.
Turning on the Administrator account is straightforward. First, open command prompt by typing cmd into the run box on the Start menu, or by right-clicking the command prompt icon that appears at the top of the Start menu, then selecting Run as administrator.
Then enter this command and press Enter:
Net user administrator /active:yes
From now on, the Administrator account will appear as an option on the Welcome screen, along with any user accounts you may have set up. Use it like any other account. Be aware that it won’t have a password yet, so it’s a good idea to set a password for it.
If you want to disable the account and hide it, enter this command at an elevated command prompt and press Enter:
Net user administrator /active:no

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