Policy Integration

In Microsoft Windows, group policies are intended to allow administrators to determine access to tools and functionality on a group basis, for either computers or users. For MMC, administrators may wish to prevent a specific group from accessing specified snap-in functionality.

Group Policy, as it relates to MMC and snap-ins, can accomplish the following:

  • Restrict author mode. Administrators can specify that author mode is restricted for any group.
  • Restrict access to specified snap-ins. Administrators can restrict access to a specified list of snap-ins.
  • Grant access to a list of permitted snap-ins. Administrators can grant access to a specified list of snap-ins. Snap-ins not included in the list have restricted access.

Be aware that policies regarding MMC and snap-ins are applicable to individual users and groups of users. The policies cannot be applied to computers.

For more information about Group Policy, see the Group Policy API documentation. The rest of this section discusses the features that snap-ins must provide for administrators to apply Group Policy to them.

Snap-ins and Group Policy

Group policies are administered using the Group Policy snap-in. The Group Policy snap-in obtains registry-based policy settings from an administrative template (.adm) file. An .adm file defines the property page the Group Policy snap-in will display to allow an administrator to manage its settings. The file also indicates the registry location where the settings are stored.

Each snap-in that can be administered with the Group Policy snap-in must provide an .adm file. The .adm file should display for the administrator two check boxes that allow the snap-in to be placed on either a "permitted" list or a "restricted" list. The list a snap-in is on is determined by a value of the Restrict_Run named Boolean value at the following registry location:


The {snapin GUID} key is the string representation of the snap-in's CLSID. The following table lists the different values that the Restrict_Run named value can take:

Value of Restrict_RunDescription
Value not presentBehavior is unrestricted.
0The snap-in is placed on the "permitted" list.
1The snap-in is placed on the "restricted" list.


The following is a sample .adm file for a snap-in:



    CATEGORY !!MMC_EventVwr

        POLICY !!MMC_EventVwr

               KEYNAME "Software\Policies\Microsoft\MMC\{975797FC-4E2A-11D0-B702-00C04FD8DBF7}"

                       #if version >= 4

                       SUPPORTED !!SUPPORTED_Win2k



                EXPLAIN !!MMC_Permit_EventVwr_Explain

                VALUENAME "Restrict_Run"

                    VALUEON   NUMERIC 0

                    VALUEOFF  NUMERIC 1          

            END POLICY        






MMC_EventVwr="Event Viewer"

MMC_Permit_EventVwr_Explain="When this checkbox is enabled, the users effected by this policy will be allowed to use the event viewer snapin unless it has been explicitly restricted."

SUPPORTED_Win2k="At least Microsoft Windows 2000"

A snap-in must provide its own .adm file for the Group Policy editor to set the snap-in's permission. Additionally, a new snap-in will not be added to the Global Policy's Restricted/Permitted Snap-in list by means of the .adm file.

Related topics

Group Policy
Distributing Your Snap-in