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For Windows Core servers, ensure you allow the firewall connections as per - http://blogs.technet.com/b/brad_rutkowski/archive/2007/10/22/unable-to-remotely-manage-a-server-core-machine-mmc-wmi-device-manager.aspx
Networking with WMI
By default, Windows sends WMI data over random ports, as explained in this Microsoft knowledge base article. You need to either:
• Configure your firewalls in such a way that all WMI traffic (over random ports) is allowed. Windows Firewall includes a remote administration exception that you can enable to allow WMI traffic, as explained in this knowledge base article. For third-party firewalls, you'll need to consult your firewall documentation.
• Configure a fixed WMI port and allow traffic through that port. Setting up a fixed port is supported by Windows Vista and more recent operating systems.
Testing Remote WMI
To test WMI connectivity
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