Instructions
Click the ̶0;Start̶1; button on your computer's toolbar and select ̶0;Run.̶1;
Enter ̶0;ipconfig/all̶1; and select ̶0;OK.̶1; This will bring up your systems current Internet settings. Make note of your IP address.
Open your web browser and enter your IP address in the address bar and press ̶0;Enter.̶1; This will bring you to your router's settings page.
Select the ̶0;Port Forwarding̶1; option and open the following ports: TCP 80, UDP 53, TCP 53, UDP 88, UDP 3074 and TCP 3074. These are the ports that your Xbox uses for communication. With these ports open, you should not have a problem connecting to Xbox Live.