Call of Duty: Modern Warfare 2 – Strict NAT problems

Modern Warfare 2 is these days pretty hot topic. Everyone is talking about it and everyone is playing it. However, there is some criticism around the game, which things are broken or badly implemented, so I will hop on the bandwagon and join with shameless bashing and criticism. ;)

Call of Duty: Modern Warfare 2 has broken UPnP support.

UPnP a protocol that enables software to talk with the internet traffic routers. For example, if you have (and most likely you do) some sort of the router in your network and you want to host a multiplayer game on the internet, you will need to tell your router that it should forward all the internet traffic for that game to your server. You will need to punch a hole in your firewall. The problem is that not many people know how to do that. UPnP is an attempt to remove this sort of complicated task. With UPnP your game server1 can tell your router which ports has to forward and where.

I use Linksys WRT54G series wireless router for internet connection. Firmware was upgraded with DD-WRT firmware and I have UPnP turned on. See the picture below.

UPnP Enabled

As you can see UPnP is enabled and Xfire client successfully enabled port forwarding for itself. Great! However this is not good enough for COD: MW2. The game itself will still report that type of your NAT is Strict. But, but, but? I have no idea why. Windows 7 firewall is also disabled so that is not the problem.

You will have to fix things the old-fashioned way – hand job. COD: MW2 requires ports from 28960 to 29000 to be forwarded to your server. Again, see the picture below.

Port forward range

Run the game, go to multiplayer and check your NAT settings in the lobby. NAT type should say open.

Lube up and Good hunting.

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  1. or the game itself []

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  • Where did you find out which ports to forward?

  • Honestly I don’t know. I googled it up somewhere.

  • On December 6, 2009 at 20:05 SOTO MOVIN' said:

    Ok im new to multiplayer online gaming. I went to my router and tried to set up my numbers, but it says i need to set the IP to a LAN IP adress. im just trying to be able to play online with randow people like i could yesterday but i have a strict NAT today and idk wtf happened… help?

  • A little bit more info would be required, which router do you have for a start. :)

  • Hi.

    I have a problem to open NAT, but only on windows7. Before that I used windows XP and there I had NAT:Open (I opened the ports on router and did all the things that had to be done), but now I installed windows7 and in the game it say NAT:Strict. Anyone have the same problem? I think that have something to do with windows firewall but I also checked and even there seems to be everything all right (there are some permissions for Modern Warfare 2).

    So, anyone can help me or put me in the right direction?

    Thanks all.

  • On December 17, 2009 at 04:26 Aurorae said:

    Hi, I’m having issues with Strict NAT for MW2 on PC.

    Some info:

    – Router: Ambit
    – I have uPnP enabled
    – I have the ports steam and MW2 uses open (Even though when I use port tester, it says they are closed, but my router says they are open)
    – I use zone alarm firewall and have steam and MW2 full access

    I still have strict NAT

    The only way to open my NAT is to shut down zone alarm firewall alltogether

  • Pero, make sure you check settings for Windows Firewall.

    Aurorae, You’ll need to check Zone Alarm if it is blocking those ports. You’ll have to tell it not to do that.

    There are always at least two places where ports can be blocked. On your computer, if you’re running any kind of firwall software or on your router if you’re using one.

    In both places ports need to be open and router must forward those ports to your computer.

  • What are you using in the pictures to forward your ports?

  • Linksys WRT54GS with dd-wrt linux.

  • Does Windows 7 have an Exceptions tab in the firewall, i have not messed with new Windows.

    Go XP!!!

  • On December 29, 2009 at 18:30 sven janssen said:

    I had the same problem ,I opened the ports for call of duty but I forgot to open the xbox live ports , 88 and anorter port. Nat might open up now ;)

  • [...] you are experiencing UPnP problems with Call of Duty: Modern Warfare 2 then you should read this post. If you don’t understand what ping bars mean and you want to tweak them and gain some [...]

  • On December 31, 2009 at 18:16 Thomas Ward said:

    How do I do that? Where’s the router? I use Vista. I have a laptop, there is also a computer in the house not used by me. Which do I use?

    See? All of this is so damn confusing.

  • i’ve done all that was mentioned but i still cannot get it to find any games when using “find match” (on xbox 360) is there anything else i can do?

  • DJ, you should be able to find matches even if you’re not hosting the game. Try disabling the firewall entirely for a quick test.

  • On January 6, 2010 at 04:11 samhay18 said:

    I tried this on my computer with 2wire and it didn;t work. can someone help.

    • On October 16, 2010 at 17:51 swiftsilentrks said:

      on a 2wire modem you can enable DMZ mode and that will clear all your problems. this disables the modems internal firewall.

  • On January 8, 2010 at 01:48 bane0030 said:

    hey i am using a netcomm NB5PLUS4 and i have opened my upnp settings and attempted to port foward following this link
    but it doesnt change my nat settings and my windows firewall is off so i dont understand why my nat settings will be set to strict …
    why cant multiplayer be like css like the good’ol days

    • Strange, I didn’t need to forward any other ports except those that I mentioned. Maybe you have a separate option for enabling/disabling firewall on the router? If the firewall is disabled it could mean that port forwarding won’t work.

  • Console must be given static ip (its own ip) eg.

    google cod mw2ports and forward them all to the consoles ip.

    Wan setting in router setup ( in internet browser) make sure NAT filtering is set to open.

    It says that this is slightly insecure than having filtering on but its only opening filtering for those mentioned ports which only access the console.

    I believe ports for the game are: 5223,3478,3479 and 3658. if you dont know what any of that means

  • I have Siemens SX 763 Wlan router, MW 2 multiplay show me that NAT is STRING, cant play with my friends, only solo, UPNP is anabled and still dont work, please HELP, THX

  • Thanks alot!! I’ve tried alot of other ports and stuff, but nothing worked. But when i tried this, it now say : NAT type: OPEN! Thank you very much!

  • WGT624v3 netgear Cant figure out my router how to open my Nat Setting for call of duty mw2 icant seem to figure out how to open it! :*( Ty

  • What ip address should i give??? is that the one that is in the pic??? or my one??? in both the cases the dynalink router is not letting it. I wanna host a game…but unable to do so. pls help

    • You will have to specify IP address of your computer where you are running MW2.

      You can find out your address by clicking Start | Run then type in cmd.exe and press enter.

      Console window will pop up and then you type in ipconfig and press enter. There you will be able to see your IP address.

  • On February 2, 2010 at 03:32 Brian B said:

    Thanks for the help, my NAT is stuck on Strict. Just to make sure I have everything straight before I mangle the settings on my router and xbox:
    Using a Lynxis 54gv5 wireless router
    1) Do I need to assign my xbox a static IP?
    2) Do I have to open ports on both the xbox and the router?
    3) I have seen a list of several different ports; how do I know when I have it correct (NAT open?)
    I’m sure I’ll think of something I forgot and need to know, but this should get me started. Thank you again!

    • Brian,

      Static IP would be advisable, but it is not required. Opening ports on Xbox? I never used an Xbox before, but if it has somekind of firewall then you’ll have to disable it or, yes, open ports on it. But I doubt that this could be the case.

      I’ve seen many port lists that should be opened for MW2, but the configuration I specified does work for me on PC. I can’t guarantee that it will work on Xbox.

  • Hey all…
    I have also problem with NAT strict, don’t know how to fix it…
    any help?? pleas???
    I have a SIEMENS Gigaset SX 763 WLAN dsl router
    pleas help

  • On March 1, 2010 at 17:52 dewgong said:


    I’ve opened all ports required for NAT type OPEN in games as MW2. My router tells me they are open, but program says they’re closed. Anyways I had NAT type open right after I’d open the ports in my router. Three days later, out of nowhere, I was back on NAT type strict.

    The game is not balanced for lean. Obviously.

  • On March 8, 2010 at 06:48 David said:

    Do not recommend enabling UPnP as it poses security risks – do it manually.

  • Hey i got a ambit Router i originally dont have thi sproblem at my home im at a cousins babysitting um whats the ports to stick in forwarding to open it from strict to Open in mw2

  • On March 19, 2010 at 21:45 charles said:

    Router type AMBIT
    I have opened my router and there is not administrative tab or anything of that sort referring to NAT or UPnP what so ever. If you could please step by step help me out i would greatly appreciate it.

  • hi.. i had same problems for 3 months.. i did everything but it was not enough to open (ports, upnp, static, firewall) and i find this on yt, and it was open.. so i hope you get it open… and here is another way to open but it didnt work for me but you should try it..

  • On April 12, 2010 at 15:10 David Lehmann said:

    Hi there, I’m sort of wanting to do the opposite of this – I pull host almost every game unless I play with someone I know who can host better so that they pull host over me. The reason I don’t want host is because about 1 minute or so into the game, everyone will drop to 1 bar of connection and I’ll get booted.

    If I block these ports, will I be able to play CoD at all? If yes, will it be hard to connect to other peoples games and parties?

  • On May 23, 2010 at 21:14 reallyjoel said:

    I temporarily put my computer on DMZ and disabled my software firewall, and I *still* get a “strict” NAT.. and my online experience with MW2 is absolutely horrendous, I never play more than one round before “lobby is closed” or I’m just out dropped without explanation. Getting in on a new server can take 1-5 tries.. This is not what I expected.. =(

  • Hey guys i really need to change my NAT to OPEN from STRICT. I dunno how to config or change NAT, my Modem is Huawei EchoLife BM622 WiMAX CPE. pls guys i badly wanna play MW2

  • my internet is with telstra and on modern warfare2 on xbox360 whenever i search for a game i will be disconnected from the party practically every time and if i get into a lobby it was ALWAYS say finding best host, count to 8 then disconnect me

  • [...] enable UPnP like Sony suggests. This usually works, but not all the time, as I mentioned before. You can turn on your UPnP settings in NAT/QoS | UPnP tab. It shoud look like [...]

  • On September 18, 2010 at 19:36 Hanoihancock said:

    I had the same “Strict NAT” problem even though I manually forwarded the recommended ports. However, by setting “Block Anonymous Internet Requests” to DISABLE, all of my problems were solved!

    • On September 24, 2010 at 23:55 ModernPro said:

      Hanoihancock, disabling the “Block Anonymous Internet Requests is just plain dumb. You want to make it easier for people to hack you? Then go right ahead. ALL you need to do in order to OPEN NAT is forward the correct ports. You dont even need to have uPnP enabled. (I have it disabled to thwart hackers.) To forward the correct ports, go to and find Modern Warfare 2. There is 1 TCP port to forward and about 6 UDP Ports that you need to forward. Make sure you forward them all and your problems are solved. C’mon people…are you TRYING to make it easier for hackers to rape your system?

  • On October 20, 2010 at 12:07 syahrein said:

    thanks! it works!

  • Can’t wait for Black Ops 2, MW3 was the first COD I played, but I’m slowly catching up and Black Ops 2 looks great!