Same problem here.. No matter what I try it continues to say strict Nat even when I've checked the port is open.
I found a web site that does help a little (in checking your ports are open ect.

http://portforward.com/

They have a free tool for checking your ports (not the obvious advertised app) plus a list of various routers and settings.

Thanks for the posts so far, but does anybody have a solution for this?

Welcome to the world of Network Address Translation. It's gigantic pain in the ass, isn't it? Well what I would do is eliminate/isolate (that is, shut off) any blocking programs, firewalls, etc until you get the game down to a non-strict NAT. Then you'll know where the problem lies, if it's your norton program you can then turn it back on and play with it until you've properly configured it/fixed the issue.

Moderate NAT would be acceptable. Open is preferred always.

Welcome to the world of Network Address Translation. It's gigantic pain in the ass, isn't it? Well what I would do is eliminate/isolate (that is, shut off) any blocking programs, firewalls, etc until you get the game down to a non-strict NAT. Then you'll know where the problem lies, if it's your norton program you can then turn it back on and play with it until you've properly configured it/fixed the issue.

Moderate NAT would be acceptable. Open is preferred always.

Turned norton off and tried it, still have a strict NAT.

*sigh* I hate BT

Having the same **** issue. I wish I could return this **** game. The single player is definitely not worth not being able to play the multi.

BLERG can somebody at least tell me if I forwarded the ports right?

Do you guys by any chance use Thomson routers?

Nope, BTHomeBub 2.

*cough* peice of **** *cough*

The ports you need to open (according to the manual) are

TCP: 80, 443, 64100, 6667, 29900, 2990, 28910

UDP: 27900, 27901, 64100

Ive opened all ports on my Belkin N1, still says NATS strict but ive never had connection problems so not to bothered

Ok so at this point I am getting really frustrated and I would like to see if some one can help me with my NAT restriction and port forwarding for Crysis 2. I checked the readme and tried inputting the information for port forwarding into my router 2 seperate times with no success. An error message kept coming up. So obviously I am dong something wrong. I have a Belkin router and the setup basically looks like this:

(Grid format)

Enable - Description - Inbound port - Type - Private IP address - Private port

The information in the readme is as follows:

Game Port Usage

For all traffic between server and client 'game' port is used
(default 64100 - net_lobby_gamespy_online_port).

Ports
SDK Service Hostname Type Local Remote

Available hbmaster3 crysis2.available.gamespy.com UDP Any 27900
NN natserver1 natneg1.gamespy.com UDP game 27901
NN natserver2 natneg2.gamespy.com UDP game 27901
NN nat neg Game client UDP game game*(other game)
QR2 hbmaster3 crysis2.master.gamespy.com UDP game 27900
QR2 Incoming queries Game client UDP game Any
CDKey keymaster key.gamespy.com UDP game 29910
SAKE Profile settings/stats crysis2.sake.gamespy.com TCP Any Any (def:80)
Chat Any IRC server peerchat.gamespy.com TCP Any 6667
GP gpmanager gpcm.gamespy.com TCP Any 29900
GP searchmanager gpsp.gamespy.com TCP Any 29901
SB gmaster3 crysis2.ms5.gamespy.com TCP Any 28910
SB Server queries game servers UDP Any game*(target server)
RSS RSS Feed lb.crysis2.ea.com TCP 80 80

Default value for 'game' is 64100 (can be adjusted).
For incoming UDP traffic, only port "game" ( default 64100)
is required to be opened.

With this information, and the type of router that I have, how would I forward these ports in my router? I would really like some help. I have been messing around with this thing on and off for 2 weeks and I am starting to get really pissed off that I bought this game just to play it on single player.

Belkin router is the problem, i have one as well, with dmz turned on UPnP turned on, port forwarding of all ports, still behind a strict nat, take the router of the loop and bam moderate nat type

Well... aside from trying that, for some games I have noticed its better to turn UPnP off. For instance, I had to port forward Halo: Reach and turn UPnP off in order for my NAT to open. Is there a difference in keeping it on for different games for multiplayer?

Hi there,

Sorry if i missed it but you said an error keeps showing up; what does the error say?

Thanks!

Which options are there?

I have Nat:Moderate

And there is Nat:Strict

Is there Nat:Open?

Hi there,

Sorry if i missed it but you said an error keeps showing up; what does the error say?

Thanks!
I think it's the standard "You appear to be behind a strict firewall" message that comes up every time upon entering multiplayer.

I have done exactly the same as BrutalWrath (port forwarding and such) to no avail in the sense of being able to play multiplayer longer than 2 minutes.

Also why does my rank keep getting reset to 5 every time I log off?