It is quite easy to change the administrator user on Windows 8, and Windows 8.1)! You can do this via the User Account Control in Windows 8 / 8.1 Control Panel.
Or if you just start the MS Explorer hot key [Windows + E] and in the address bar [ALT + D] enter the the address:
Control Panel\All Control Panel Items\User Accounts\Manage Accounts
Or, open the Windows 8/8.1 Control Panel and click on (open) Manage accounts.
Best! Use hot-key [Windows + R] and command control.exe nusrmgr.cpl (... see Image-1 Arrow-1) and
click on the text "Manage another account" (... see Image-1 Arrow-1)!
See also: ... Manage Users in Windows-8 (add, remove, enable, delete)!
in "\Manage Accounts" Window click on new Administrator for example Markus (see Image-3 Arrow-1).
And now click in the Window "Change an Account" the text "Change the account type" (see Image-4 Arrow-1).
The last step Change Account type (e.g. Markus), to the Administrator (see Image-5 Arrow-1).
Whether you sign in to your PC with an email address (to access your Microsoft account) or a user name and password, for everyday tasks, it's best to use a standard account. A standard account can help prevent people from making critical changes, such as deleting files that are required for the PC to work. You can create a standard account for each person who uses your PC.
When you're signed in with a standard account, you can do almost anything that you can do with an administrator account. But if you want to do something that affects other people using the PC, such as installing software or changing security settings, you might be asked to enter a password for an administrator account.
FAQ 85: Updated on: October 10th 2013 14:55