Lets you selectively permit or prohibit the use of Microsoft Management Console (MMC) snap-ins.-- If you enable this setting all snap-ins are prohibited except those that you explicitly permit. Use this setting if you plan to prohibit use of most snap-ins. To explicitly permit a snap-in open the Restricted/Permitted snap-ins setting folder and enable the settings representing the snap-in you want to permit. If a snap-in setting in the folder is disabled or not configured the snap-in is prohibited.-- If you disable this setting or do not configure it all snap-ins are permitted except those that you explicitly prohibit. Use this setting if you plan to permit use of most snap-ins. To explicitly prohibit a snap-in open the Restricted/Permitted snap-ins setting folder and then disable the settings representing the snap-ins you want to prohibit. If a snap-in setting in the folder is enabled or not configured the snap-in is permitted.When a snap-in is prohibited it does not appear in the Add/Remove Snap-in window in MMC. Also when a user opens a console file that includes a prohibited snap-in the console file opens but the prohibited snap-in does not appear.Note: If you enable this setting and you do not enable any settings in the Restricted/Permitted snap-ins folder users cannot use any MMC snap-ins.
Windows Components\Microsoft Management Console
At least Windows 2000