Just i thought here, not sure if this is helpful info but,
i would try going into properties on the shortcut and play with the compatibility mode try running it in win98 or something, dont know if that will fix but worth a try.
also, i have noticed, as i am running my own server and have a few friends and family playing on here often, and one of the bigger issues i face trying to get them connected is with the A.M.D duel core,
so this is what we have to do in order to get the game to run on duel core AMD
go to the site and download and install the Duel core optimizer,
http://www.amd.com/us-en/Processors/...1_9706,00.html
i hope this link works i dont post on here much, and i hope that these ideas might help as well, good luck with it