Windows has a single default access control list (ACL) on all power policy objects. The ACL grants read, write, and change permissions to members of the Authenticated Users group. All other users are granted read-only permission. Applications that call power policy functions can determine whether a user has permissions for a specified power setting by using the PowerSettingAccessCheck function.
Power settings may be overridden via Group Policy. Overrides can be set through domain group policy or local group policy. PowerSettingAccessCheck will report if a specified power setting has a group policy override.
The command line tool PowerCfg.exe displays an error message when a command cannot be completed either because the user did not have permissions to change the power setting or because the power setting has a group policy override.
The Power Options application in Control Panel does not provide support for configuring power policy access permissions. Changing permissions must be done via PowerCfg.exe.
Windows Server 2003 and Windows XP:
An administrator can override certain power policy settings in a user's power schemes. These settings are defined in the ADMINISTRATOR_POWER_POLICY structure and include the minimum and maximum video time-out values, the minimum and maximum disk spindown time-out values, and the minimum and maximum system sleep states. These values take priority over any settings selected by the user in the Power Options application in Control Panel.
To determine whether any administrator overrides are currently active on the system, use the CallNtPowerInformation function to retrieve the current ADMINISTRATOR_POWER_POLICY structure and examine the structure members for nonzero values.
To set administrator override policy settings, call the CallNtPowerInformation function with an ADMINISTRATOR_POWER_POLICY structure that contains the desired policy settings. (Callers must have administrator privileges.)