Setting your NAT Type to open can be difficult or even impossible. Although the general idea is simple to "port forward" Call of Duty's port (UDP 3074) to your gaming computer, the specific steps are different for everyone. (Except for the full page ads) this website is the best guide I know...

http://portforward.com/

To confirm that your network and computer are properly forwarding UDP port 3074, you can use this tool...

http://www.pcwintech.com/simple-port-tester

Unfortunately, even if you do everything perfectly and it STILL doesn't work, the problem can be caused by your internet service (ISP). In that case, you have to contact them for support.

Good luck!

thanks and checking your guideline hope it works

Originally posted by AquaeAtrae:

Setting your NAT Type to open can be difficult or even impossible. Although the general idea is simple to "port forward" Call of Duty's port (UDP 3074) to your gaming computer, the specific steps are different for everyone. (Except for the full page ads) this website is the best guide I know...

http://portforward.com/

To confirm that your network and computer are properly forwarding UDP port 3074, you can use this tool...

http://www.pcwintech.com/simple-port-tester

Unfortunately, even if you do everything perfectly and it STILL doesn't work, the problem can be caused by your internet service (ISP). In that case, you have to contact them for support.

Good luck!

i tried tool and 3074 UDP and TCP both FAILED. what should i tell to my ISP to get my NAT TYPE OPEN???

You need "UDP port 3074 forwarded" to your gaming computer from the external internet.

and set up a DMZ

Actually, DMZ (forwarding all ports through your NAT firewall) is redundant if you're able to forward the individual port. It forwards ALL ports to your computer.

Assigning your gaming comptuer as a "demilitarized zone" exposes it, in it's entirety, to the internet. So it is considered less secure. Whereas, port forwarding only exposes the specific port. Best option: if UPnP is enabled and working correctly, ports are forwarded automatically and the needed port is only forwarded temporarily, as needed.

Although slightly easier than forwarding each needed port, I only recommend DMZ to users who understand their firewall security very well and have only one computer at home. If you do not have a good firewall with intrusion prevention running on the gaming computer, it's dangerous.

ok and there are 4 ports that shuold open

Originally posted by AquaeAtrae:

Actually, DMZ (forwarding all ports through your NAT firewall) is redundant if you're able to forward the individual port. It forwards ALL ports to your computer.

Assigning your gaming comptuer as a "demilitarized zone" exposes it, in it's entirety, to the internet. So it is considered less secure. Whereas, port forwarding only exposes the specific port. Best option: if UPnP is enabled and working correctly, ports are forwarded automatically and the needed port is only forwarded temporarily, as needed.

Although slightly easier than forwarding each needed port, I only recommend DMZ to users who understand their firewall security very well and have only one computer at home. If you do not have a good firewall with intrusion prevention running on the gaming computer, it's dangerous.

i got my NAT TYPE OPEN without port forwarding and without telling ISP to allow me for NAT TYPE OPEN... i dont know how its open but now im very happy and playing my favourite ZOMBIES with FRIENDS.. THANKS TO ALL FOR YOUR HELP....

1 other thing I've had the NAT problem myself sometimes its as annoying as shutting down steam rebooting the computer and restarting steam. Also, I find dependant on the number of users on your internet connection this too can cause NAT issues. Good luck

Yeah, I see Moderate NAT type randomly still myself despite knowing the correct ports are forwarding. Often restarting fixes the bug.