If you don't have a firewall installed, the windows firewall is probably running. Look in the security center on the control panel, and see if the windows firewall is running. If so, add the port you are using to the exclusions list and try it again.
I'm going to become rich when I create a device that allows me to punch people in the face over the internet. "If an Indian asked a programming question in the forest, would it still be urgent?" - John Simmons / outlaw programmer