How to open ports varies from router to router so visit http://portforward.com/ and follow the instructions on that site for you make and model of router.
UDP ports 4658, 6500 TCP port 4658 are the ports to be opened.
If you continue to have problems connecting to servers or creating them, try bypassing your router or firewall by connecting your PC directly to your broadband connection.
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How to open ports varies from router to router so visit http://portforward.com/ and follow the instructions on that site for you make and model of router.
UDP ports 4658, 6500
TCP port 4658
are the ports to be opened.
If you continue to have problems connecting to servers or creating them, try bypassing your router or firewall by connecting your PC directly to your broadband connection.