After you log on by clicking your name on the Welcome screen, you can add more users quite easily. The Getting Started item near the top of the Start menu invites you to add new users, but you don’t need an invitation to add them at any time. Here’s how.
1. Choose Start> Control Panel and, under the User Accounts and Family Safety heading, click the Add or Remove User Accounts option.
2. Click the Create a New Account option.
3. Type a name for the new account.
You can give a new account just about any name you like: first name, last name, nickname, titles, abbreviations. No sweat, as long as you don’t use the characters!
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4. Tell Windows whether you want the account to be a standard user account or an administrator account.
The choice of standard versus administrator account status isn’t nearly as straightforward as the Microsoft description would lead you to believe.
5. Click the Create Account button.
You’re done. The name now appears on the Welcome screen.
This topic is more than a bit confusing, but you aren’t allowed to create a new account named Administrator. There’s a good reason why. Windows 7 prevents you from making a new account with that name: You already have one. Even though Windows 7 goes to great lengths to hide the account named Administrator, it’s there, and you bump into it if you ever have to restore your system.