Why can't my wi-fi connect to the game server in GoldenEye 007?

I have the new Nintendo Wii game, GoldenEye 007. I've had trouble connecting to the game server for Multiplayer Wi-Fi mode. When I try, it will display: "Starting Network" for a minute or so, and then an error message pops up reading: "Unable to connect to the game server". Now I HAVE done a little research on it, and I found that the solution would be to open up the following ports: Nintendo Wi-Fi 443, 3074 TCP; and James Bond: GoldenEye 3074 UDP. I found out how to do that by going into Windows Firewall on my control panel, and I was able to connect a couple times, but the next day.... no such luck. The same error message came up, and I noticed that every time I tried to connect, my computer screen would give me a message: "A Network Cable is unplugged." Diagnosis, anyone?