If there is a firewall or a router between the Xbox
console and the networking hardware, and if the Xbox LIVE
test reports an NAT problem, you may have to make
configuration changes to enable communication on the
specific network ports that are required by Xbox LIVE. This
reconfiguration is known as "port forwarding." If you use an
Xbox LIVE-compatible device or a Windows Vista-compatible
device that has the correct firmware installed, you should
not have to make these changes.
For more information about how to determine whether your
networking hardware is compatible with Xbox LIVE, click the
following article number to view the article in the
Microsoft Knowledge Base:
944293(http://support.microsoft.com/kb/944293/
) How to find out if your networking hardware is
compatible with the Xbox LIVE Service
If your device is not on the compatible list, and if you
experience the symptoms that are described in the
"Introduction" section, you can try to open the following
ports:
TCP 80
UDP 88
UDP 3074
TCP 3074
UDP 53
TCP 53
You can only all these ports manually or open the DMZ
of the router following these steps: