How do I change my NAT from strict to open (or even moderate) with a AT&T Modem on XBox Live?

I have a modem, not a router...


Everything worked fine on XBox live: I could play with all my friends fine and matchmaking was very smooth.


However, about two days ago, my friend and I could for some reason no longer play together... It turned out I had strict NAT.


My first question is why did it stop working?





Also, we were going to get katana (and because of this he got it before me)





Second, When I made test my connection, it said wired, and that is correct, but it said Strict NAT, which is also correct. I can still play matchmaking and also with some of my friend, but he's my best friend and I can't play with him because of NAT. We are really good together as a team in doubles!





How do I change the NAT from strict to open (and preferably the easiest way because I'm no technology wiz)





Help is GREATLY appreciated, and thank you!

How do I change my NAT from strict to open (or even moderate) with a AT%26amp;T Modem on XBox Live?
you have to get a router and port forrward the static ip adress to ur XBOX 360...... then switch off firewall..... go to portforward website ull get more infos there
Reply:You need to open the firewall on the modem, look up the specific ports you need online, some modems or routers allow you to easily select "xbox" and it will open the ports for you. You can probably do this from a PC connected to the modem, but you need to know the login username and password. Consult with your ISP, they can probably help.

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