Group Policy error | RPC Server is unavailable.

When you attempt to connect to another domain computer using the GP Results Wizard. It fails with following error :

Failed to connect to Domain\Computer due to the error listed below. Ensure that the Windows Management Instrumentation (WMI) service is enable on the target computer and consult the event log of the target computer for further details. Refer below image.
Details:  The RPC server is unavailable.

RPC uses port 135 and 445. Firewall blocking the RPC traffic. So we have to enable the Remote Administration Firewall Rule.

Windows XP / Windows Server 2003

For Windows 7/Windows Server 2008 uses following command at the system prompt:

netsh firewall set service type = fileandprint mode = enable
netsh firewall set service type = remoteadmin mode = enable

1. Open the Group Policy Object Editor snap-in to edit the Group Policy object (GPO) that is used to manage Windows Firewall settings in your organization
2. Open Computer Configuration, open Administrative Templates, open Network, open Network Connections, open Windows Firewall, and then open Domain Profile.
3. In the details pane, double-click Windows Firewall: Allow remote administration exception.
4. In the Windows Firewall: Allow remote administration exception properties dialog box, on the Settings tab, click Enabled.

Note :  “netsh firewall” is deprecated after windows XP / Windows server 2003. Use “netsh advfirewall firewall” instead.

For more information on using “netsh advfirewall firewall” commands instead of “netsh firewall”,

see KB article 947709 at http://go.microsoft.com/fwlink/?linkid=121488.

http://technet.microsoft.com/en-us/library/cc738900%28v=ws.10%29.aspx

Windows 7 / Windows Server 2008

For Windows 7/Windows Server 2008 uses following command at the system prompt:

netsh advfirewall firewall set rule group="File and Printer sharing" new enable=yes
netsh advfirewall firewall set rule group="windows management instrumentation (wmi)" new enable=yes    
netsh advfirewall set domainprofile settings remotemanagement enable

Note : The requested above operation requires elevation (Run as administrator).

If you would rather use the Firewall UI than the netsh commands above, use the following steps on the server:

1. In the Control Panel, click Security and then click Windows Firewall.
2. Click Change Settings, and then click the Exceptions tab.
3. In the Exceptions window, select the check box for Windows Management Instrumentation (WMI) to enable WMI traffic through the firewall. To disable WMI traffic, clear the check box.