In Windows, how can I run an administrator task from a non-admin account?

In Windows, certain tasks, including installing or upgrading software and configuring certain operating system parameters, require that you log in as an administrator.

However, you can also accomplish most of these tasks as a regular user by temporarily logging in with administrative rights to carry out your task, while keeping the actual administrator account insulated from security risks. (See In Windows, why should I avoid running my computer as an administrator?)

• In Vista, when you begin a task requiring administrative privilege, you will be prompted to enter the username and password for your administrative local account.

  If a particular software application on your computer requires you to be logged in as an administrator, you can right-click the application and select Run as administrator.

• Windows XP and 2000 provide a Secondary Logon service (also known as "run as") that lets you run programs as different users. To use it, do one of the following:
  
  
  • Navigate to the program you wish to launch with different privileges. Click it once to select it, then hold down the Shift key and right-click the program. You'll see a contextual menu from which you can select Run as... and then choose a different account.
    
    
  • From the Start menu, select Run... , and enter the following command: runas /user:username cmd

    Replace username with the name of the account you want to use. You can replace cmd with any command you'd like to run (if it contains spaces between characters, enclose it in double quotes). Click OK. When prompted, enter the password for the account you've chosen. This method will start a new command shell in a new session, from which you can launch programs.

For more on this topic, see Wikipedia's User Account Control page.

Also see:

• Best practices for computer security
• What is the principle of least privilege?
• On a computer, what are administrators and administrative rights?
• In Windows XP or Vista, how do I create an administrator account?
• In Windows 2000, XP, or Vista, how do I set the administrator password?
• At IU, why do I need to know the administrator account on my computer?