Quote Originally Posted by Puzz3D
M2TW communicates over a different port than does MTW. The port is a number that's included in each data packet, and it's used to direct incoming packets to the appropriate program. Firewalls block data packets that originate a request from outside the firewall unless the firewall has been configured to pass the included port number. As I recall, MTW uses port 18321 and MTW/VI uses port 18322, and these ports have to be open for both UDP and TCP. GameSpy also requires about 10 additional ports to be opened, but I don't know if they affect visibility of hosted games. I don't know what port or ports M2TW uses or if it requires both UDP and TCP. So, it's possible that a firewall could block MTW/VI hosting and not M2TW hosting, and that would be consistent with all the MTW/VI installs working.
So, why have I not had a problem hosting before? All I have ever had to do with my firewalls is set them to 'Allow' or 'Not block' the servers that I am connecting to.

Quote Originally Posted by Puzz3D
Right now we only have 6 people playing Samurai Wars MP regularly. We all have MSN and can arrange games over that, and CBR hosts a teamspeak server on Sunday for those who have a headset and microphone. I think just about everyone can host, so it's not actually necessary to be able to host during this session.
No, but it would be necessary for one of us to be able to host at other times that suit us.