If you connect to the server by: /server irc.server.com . Then try connect to the servers IP, type /dns server.address in any window and look in your status window. you can also try change port to the server, 6667 is often used, but if you look in the motd (message of the day) you maybe find more listening ports in it. (if the server are added in the server list in mirc, then you maybe can see the ports there). I hope this can help you.