Use the Details pane to work with discovered groups. You can create replicas of the computer groups. Replica groups are regular computer groups that are based on the membership of a discovered group. For example, if you want to give a user access to all the computers in Exchange Routing Group 1, you need a “real” computer group to add to the user's console scope. You cannot add discovered groups directly, so you must create a replica group from the discovered group.
To create a replica of a computer group