Ports for "Age of Empires III"
The ports that you need to forward for Age of Empires III are TCP ports 80 and 2300 and UDP ports in the range 2300 to 2310. To open these ports, navigate your Web browser to your router configuration page, enter your network administrator credentials and go to "Port Forwarding" or "Gaming." If you are not a network administrator, contact your IT staff or the network administrator and provide a list of ports you need opened. This process opens the ports to incoming and outgoing Internet traffic that normally would be blocked by a firewall to prevent hackers from accessing your internal network and potentially causing harm or stealing data. To forward a port is basically to open another lane on the highway. Opening only necessary ports ensures a safe traffic flow.
Windows Firewall Exception
In addition to opening the above ports, it may be necessary to add a Windows Firewall exception to the game. This makes sure that the game itself won't be blocked from accessing the Internet by Windows. Open the version of Windows Firewall specific to your operating system (normally accessible through the Control Panel) and click the "Exceptions" tab. Click "Add Exception" or a similar option and browse to your game client, which ends in ".exe," in the folder that you originally installed the game in.
Updating Game Client
If you are still experiencing trouble connecting to the Internet through "Age of Empires III," update your game. Close the game client if it is open and navigate your Web browser to the game's updates page (see Resources) to obtain a patch to update to the latest version.
Manual Port Override
If you are unable to forward the ports mentioned in the first section, manually override these ports and substitute them for your own. This is especially useful if you have conflicts between ports being used by different programs, because only one program at a time can use a certain port. Go to your game directory (the folder where you installed the game) and open user.cfg in a text editor such as "Notepad." At the end of the document, click "Enter" and type the following line: OverridePort=[a port number that you specify]. Replace the bracketed information with your desired port number. Save and exit the document and restart the game. You should now be able to use the custom port.