A: User Access Control is a key technology in the later Windows OSs, including Windows 8. It helps limit normal privileges available during a logon session for privileged users, such as an administrator. It was originally introduced in Windows Vista and prompted users frequently when elevation of privileges was required. The number of prompts was reduced in Windows 7 with a more flexible level of control of the level of prompting in the User Accounts control panel applet, via the Change User Account Control settings option, which the following screen shot shows.

Windows 7 UAC Settings

When the setting is set to Never notify, UAC is actually disabled. The same setting is available in Windows 8 (although it has different) text.

However, the changes made to the system are very different from those made in Windows 7. With Windows 8, the Never notify setting does NOT disable UAC but instead removes any prompts to the user, so when an application makes a request for privilege elevation it will just happen automatically.

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