Xbox live through macbook

Hi everyone! I know this is an old issue, but I've been tearing my air out for days! I have managed to get connected to xbox live but the NAT settings are strict! I'm sure it was working a few days ago, but now I can't get any games. I have changed the MTU to 1374 and back again and opened every port suggested. So,

is it possible to get an open NAT status when connecting via a macbook?

am I opening ports correctly? I have a thomson gateway tg585 v7 router. I opened the gaming and application sharing tab and created a new application with the various ports. Do I associate the 'application' with the IP address of my macbook, or the xbox?

thanks for all your help boys and girls

Hey Tom,

I had a similar problem although I was not trying to connect xbox live and my mac. The problem lies in the router, I first contacted my internet provided in response to this message about the nat type and they then told me to speak to the manufacturer of the router. After calling the manufacturer I was able to open the nat with their help. It was a fairly complex process requiring passwords that I didn't have so I would strongly recommend calling them. Hope this helps.