You can do this in any version of Vista. However, caution is the keyword
here and you should not use the built-in administrator account other than on
a temporary basis.
Go to Start and type cmd
In the programs list, right click on CMD and select Run As Administrator.
In the command prompt window, type the following command.
net user administrator /active:yes
(Note the spaces and colon)
Press Enter.
Log off of your user account and you will see the Administrator account on
the Welcome screen. This account will not have a password associated with
it. The first thing you need to do is go into Control Panel / User Accounts
and create a strong password for this account.
Resource :
Enable Admin on any VistaHow about that little bit of helpful news! :)