There is always an hidden Administrator account associated for every Windows since Windows Vista. By default, the build-in Administrator account is hidden. Administrator account is used for making system wide changes that could affect all other users on the computer. If you are a Mac or Linux user, Windows’s Administrator is more or less the equivalent of the root user for UNIX/Linux system. In Windows 8.1, you can enable the default Windows Administrator account with the following steps.
Log in to an existing user > Start Menu > type “cmd” find “Command Prompt” and right click make sure launch as “Administrator”.
Now type net user administrator /active:yes this will tell Windows to enable the hidden default build-in Windows Administrator account. You need to logout the current user in order to see the newly “added” Administrator account. You can log out your existing user by going to Start Screen > Click on your personal icon on the top right > Sign out.
Once you have logged out, you will see a new account named “Administrator” appear from the login screen. Click the Administrator user to log-in.
This user will have a brand new user profile that’s independent from all other users, and by default Windows will launch the user to a default setting. From here you can do tasks that only can be done through administrators account permissions. Once you are done, you can Sign out Administrator account the same way as you do when switching users from the stander user.
How To Disable Build-in Windows Administrator Account
You can also disable or hide the build-in Windows Administrator account if you no longer need to use this user on a daily basis. And it is recommended to do so, you can do that by repeat the same step earlier of launching the “Administrator Command Prompt” and enter the following command net user administrator /active:no
When you done enter the command in the command prompt, the “Administrator” account will not show up and it will be completely hidden from the stander users.
Note that the same step also works on Windows 7 computers to enable or disable their local built-in admin account.