Keep getting "Game disconnected: could not join server."

you can try those methods: as i posted or try this link http://answers.ea.com/t5/Battlefield-3/Game-disconnected-could-not-join-server/m-p/10580#M1703

Problem 3:
Get disconnected very often without a reason.

Solution 1:
-Download PBsetup from here: http://www.evenbalance.com/index.php?page=pbsetup.php [evenbalance.com]
-Extract the files in a folder
-Run PBSETUP.exe
-Click "add a game"
-Select "Battlefield 3". The path of the game should be detected automatically, if not, point it to the right path.
-Click check for updates
-Once the downloads are over, you'll get a message "battlefield 3 is up to date" or similiar. you may now close the application.

Solution 2
-Click on the windows logo/start button
-In the searchbar, type services.msc
-Press ENTER
-A list of services should now be in front of you.
-Click "extended" tab
-Search for "UPnP host devices" or something similiar (the description is something like: Allow hosting of UPnP devices blablabla)
-Right click it
-Click Properties
-I don't know how to translate this, but there is an option like "startup", in the general tab. You can choose between: Automatic (delayed startup), Automatic, Manually, Disabled. You must choose Disabled.
-Click on "stop service"
-Click "apply" and close that little windows.
-Search for "SSPD discovery" and do the same things that you did above.
-Close everything
-Reboot.

Solution 3
-Open chrome/IE/firefox
-Type in the adress bar 192.168.0.1 and press enter. if nothing work with that IP, try with one of these: 192.168.1.1, 127.0.0.1, 127.0.1.1. With one of these IPs you should be able to open up your router's page.
-Log into the router panel (username is usually "admin" or "administrator", aswell as the password)
-Once you are in, you should search for an option called UPnP, and disable it. it might be somewhere in the advanced options, i really can't help you with this one because it's not on my router, and every router it's different, so you might or might not have it.

In case you still have the problem...well...go to the nearest churc and turn on a candle, then prey for a bit.