If multiple network connections exist on a server, Windows Firewall will apply the least privilege / most secure firewall policy to all connections. Thus, if a server has two network connections, one with domain access and one with private (no domain) access, Windows will see the second NIC as residing in a “Private” or “Public” network, not “Domain”. The impact of this is that Windows will then take the Group Policy firewall settings applying to “Private” or “Public” and apply them to the “Domain” connection as well. The only way to decrease/disable the firewall restriction is to configure the policy for the “Public” or “Private” network as well.