I can´t join warfighter multiplayer

You might get more reply's if you write this on the Medal of honor forum. But here is somethings you could try. It sounds like a driver problem to me.

This list is made by a good friend Carbonic:

-Please write descriptive (also the subject line) so the right people find your question and knows what it contain
-Try restarting your computer and network equipment (routers, switches etc.)
-Try another browser (Chrome/FireFox/IE)
-Can't find your game? Make sure you have bought BF3: Premium Edition and not just Premium.
-Check the Origin server status: http://www.origin.com/us/status
-Try cleaning your browsers' cache and temporary files using CCleaner (http://www.piriform.com/ccleaner)
-Try repairing your game in Origin (right click -> repair)
-Try reloading your games in Origin
-Check if Punkbuster is running correctly and update it manually (https://help.ea.com/in/article/punkbuster-technical-issues)
-Make sure Origin doesn't have connection issues (https://help.ea.com/article/connection-issues-with-origin)
-Make sure the correct ports for BF3 is open (https://help.ea.com/article/online-ports-for-battlefield-3)
-Try reinstalling Origin by manually uninstalling first (https://help.ea.com/article/manually-uninstalling-origin) + make sure it's the newest version
-Try reinstalling the game by manually uninstalling first (https://help.ea.com/article/How-to-manually-uninstall-Battlefield-3)
-Try setting bf3.exe as a trusted application in the windows(/other) firewall
-If you have a Realtek soundcard try disabling it in the BIOS
-Try deleting the BF3 Settings folder in C:/Users/USERNAME/My Documents/Battlefield 3
-Try doing a UOtrace to EA's servers to check for problems - https://help.ea.com/article/how-to-uo-trace
-Update ALL your drivers especially the graphics card but also components like soundcards, network card, motherboard/chipset, headset and mouse+keyboard, to the newest version, if the problem came with a new driver then remove that driver and downgrade to the driver that worked.
-Use Windows eventviewer to look at the error in xml and copy/paste the solution here
-Run Origin and Battlefield 3 as administrator (http://technet.microsoft.com/en-us/magazine/ff431742.aspx)
-Go to the cloud button on BF3 and uncheck the “enable cloud storage for all games” box. Launch the game, quit it and re-enable the cloud storage box. Make sure to use the local data when the information box popping up.
-Check the READ FIRST post http://answers.ea.com/t5/Battlefield-3/READ-FIRST-Known-issues-guides-and-FAQs/m-p/215092/highlight/... most answers are in there
-Look at this handy dandy post: http://answers.ea.com/t5/Battlefield-3/Battlefield-3-fixes-guide-read-carefully/td-p/76264
-Banned? Read this: (https://help.ea.com/in/article/information-about-banned-or-suspended-accounts)

If none of this worked, post relevant logfiles, screenshots, descriptions, exact errormessages, and all other relevant information(like platform) - even if it's stupid and obvious (there's alot of clueless people on the internet ;-) )

Please accept solutions if they are correct and press the XP button if somebody helped you. This way you help others in the same situation.

Kind regards, Tviggah