INetFwRule firewallRule = ( INetFwRule ) Activator . CreateInstance ( Type . GetTypeFromProgID ( "HNetCfg.FWRule" ));
firewallRule . Action = NET_FW_ACTION_ . NET_FW_ACTION_ALLOW ;
firewallRule . Description = "Allow notepad" ;
firewallRule . ApplicationName = @"C:\Windows\notepad.exe" ;
firewallRule . Enabled = true ;
firewallRule . InterfaceTypes = "All" ;
firewallRule . Name = "Notepad" ;
INetFwPolicy2 firewallPolicy = ( INetFwPolicy2 ) Activator . CreateInstance (
Type . GetTypeFromProgID ( "HNetCfg.FwPolicy2" ));
firewallPolicy . Rules . Add ( firewallRule );