Use /gd to delete a server-level or collection-level group.
To use the /gd command, you must have the View collection-level information and Edit collection-level information or the View instance-level information and Edit instance-level information permissions set to Allow, depending on whether you are using the /collection or /server parameter, respectively. For more information, see Team Foundation Server Permissions.
Specifies the group identity. For more information about valid identity specifiers, see Changing Groups and Permissions with TFSSecurity.
Required if /server is not used. Specifies the URL of a team project collection in the following format: http://ServerName:Port/VirtualDirectoryName/CollectionName
Required if /collection is not used. Specifies the URL of an application-tier server in the following format: http://ServerName:Port/VirtualDirectoryName
The following example deletes a group from the team project collection. The group is identified by "S-1-5-21-2127521184-1604012920-1887927527-588340", the security identifier (SID). For more information about finding the SID of a group, see /im Command. You can also use the friendly name to delete a group.
>TFSSecurity /gd S-1-5-21-2127521184-1604012920-1887927527-588340 /collection:CollectionURL