Symptoms

When using the ellipsis button (...) in Workgroup Manager to browse and add computers to a computer group, all computers on the local network may not appear in the list.

Resolution

When using the ellipsis button (...) in Workgroup Manager to browse and add computers to a computer group, clients will not appear in the list unless the following conditions are met.

Mac OS X v10.6 and later

• The client is bound to a server using Directory Utility

Note: OS X Lion clients should be updated to v10.7.3 or later. Clients running 10.7 through 10.7.2 may not appear in the list when browsing.
 

Mac OS X v10.5 

• The client is bound to a server using Directory Utility
  or
• The client receives LDAP information via DHCP (also referred to as "option 95")

Additional Information

Workgroup Manager is not included with OS X Server (Mountain Lion).