Windows OS doesn’t limit the number of administrator accounts, you can set as many as you can for your requirement.

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It’s simple to set an administrator account: Start>Settings>Control Panel>User Accounts>Pick a Task>Create a new account, in the text box ‘Name the new account’, enter a user name and click ‘Next’, keep the checkbox ‘Computer administrator’, and click ‘Create Account’ to set a new Windows administrator account.

Return to the User Accounts window, and click the user name you recently created, and go on to click ‘Create a password’, after that set a password for your user name.
What rights does Windows administrator have?
With a computer administrator account, you can:

a. Create, change, and delete accounts

a. Make system-wide changes

a. Install programs and access all files.

The Welcome screen appears the names of each one with a user account for this computer. This screen shows when you start the computer or switch users. Windows administrator user names will show on this window.

What about user accounts which are neither administrator account nor guest account?
With user accounts, you can:

a. Customize the way Windows and the desktop look for each user on your computer.

a. Have your own lists of Web Favorites and recently visited Web sites.

a. Help protect your important computer settings.

a. Log on faster, and quickly switch between users without closing your program.

What’s the difference between the administrator account and guest account?
Administrators have entire control control of the whole system, with administrator account, you can see and use all users’ documents and folders, change files, and install and remove programs. However, if with Guest account, you can only use the ready programs installed on the computer, not capable to view and change files and folders created by other users.

How comes I log onto Windows with the hidden administrator account?
When starting Windows, the Welcome Screen only lists the regular user names by default. The administrator's account is unseen. Press key combination Ctrl+Alt+Delete (Delete two times) to show Login Dialog Window and you will observe a user name box and a password box. Type ‘Administrator’ in the user name text box and enter the password in the Password text box. After that you log onto Windows with administrator account.

What if I forgot Windows password? What can I do if the administrator password is lost?
If you don’t remember your password on a computer that is part of a work or is a separate computer, check your password hint.
If you have a password reset disk, you can use it to generate a new password for your account. Your personalized computer settings will be keep.

If your password hint does not help you keep in mind your password and you did not make a password reset disk, you will require having somebody with a computer administrator account make a new password for you. For security reasons, a computer administrator cannot recuperate your password if you forget it; he or she can only make a new one for you.

If so unfortunately, you have your lost administrator password, The suitable and simple way is to get help from windows password recovery software, like Windows Password Reset 7.0, which is professional and simply to crack windows XP administrator password in one second.