Backward compatibility, CoD3

Hi there Gryphon11,

Thanks for the reply. I understand there is an issue with connecting to multiplayer matches due to a strict NAT.

- The NAT type is established based on the network configuration and connection. Therefore, if the console's NAT is strict it will affect all users on that one console.

- No they will not affect other games.

- If the problem persists, take a look at the following article:

Network ports used by Xbox Live on Xbox One.

You can also find information about opening ports on your router at the
Port Forward website. This website lists commonly used ports for various apps and games, but if your router isn't listed or you need more help, contact your Internet service provider or router manufacturer.

Hope this helps.

I appreciate the info. It's a bit intimidating but I'll follow up. I have a couple questions:

- will all players have to have the same NAT and UPnP settings?

-will those setting changes effect other games we've had success with? And in that vein, is COD 3 something unique?

As the Microsoft Agent stated, your NAT type is the issue. This support page has good information about NAT types and how to fix it https://support.xbox.com/en-US/xbox-one/networking/nat-error-solution

Hi Gryphon,

Thank you for coming to the forums. Unfortunately having a Strict NAT type will be a barrier when trying to play with others on Xbox Live who have Open NAT type since the Xbox is not connecting to the network securely and a Strict NAT type will prevent the
network from being able to communicate with the other networks trying to play on the same server.

First thing to look into which isn't that difficult is to make sure your router has UPnP toggled on since some routers provided by ISP's don't have it turned on by default. The option is there but you need to log into your router settings and find the switch
for UPnP that is usually found under the general Networking settings after you log in. Refer to your router manual or look online on their manufacturers support page with assistance in logging into the router settings. Some routers have apps you can manage
this but mainly you will need to enter the router's IP address into a web browser and then a window to log in will appear. AT&T has been known to give out routers that don't have this setting on by default.

Follow this
guide for basic UPnP troubleshooting on the Xbox.

Make sure the UPnP setting is on and let us know if this helps!

Hi,

firstly, make sure you're using the 360 mini-guide to send invites, using the Invites options on the Xbox one dashboard won't show up on Xbox 360 titles.

Secondly, you're going to have to fix the Strict Nat issue your Xbox One if you want to be able send, accept and join games. The Nat Issue is the main reason for your Multi-player issues. For that, you should start

here.