Hey, try checking this topic out. http://www.gamerenders.com/forum/index.php?showtopic=233567 Hope I helped, Snipe.
Turn it off and try and send the credits, if it works, you know you need to tweak your settings a little.
I still got my same computer still the same firewall and it never happend before. <_< But i will try again later. Thanks for all the help