If network discovery on Windows Server 2008 R2 is not enabled, the ZyLAB Services that retrieve indexes, services and/or user management database tables over a network may be affected.
One of the possible causes could be that Windows Server network discovery setting keep returning to the OFF state while trying to enable this setting.
The following services needed to be started in order for it to work:
Network discovery requires that the DNS Client, Function Discovery Resource Publication, SSDP Discovery, and UPnP Device Host services are started, that network discovery is allowed to communicate through Windows Firewall, and that other firewalls are not interfering with network discovery. If some but not all of these are true, the network discovery state will be shown as Custom. See http://windows.microsoft.com/en-us/windows7/what-is-network-discovery for more information.
6.2; 6.2 Service Pack 1; 6.2 Service Pack 2