De readme file kan toch iet handig zijn
2.10. Firewall/NAT Port Number Info:
The game will need to talk to external servers that use the following port numbers. These ports need to be open in your firewall in order to play on Generals Online:
TCP ports:
80, 6667, 28910, 29900, 29920
UDP ports:
4321, 27900
If your firewall does not allow outgoing packets to open ports to incoming traffic, or you experience problems connecting to other players, you will have to specify which port you want Command & Conquer Generals to use for communicating with other players. To do this, perform the following steps.
Go to your “My Documents” directory, and go to the “Command and Conquer Generals Data” directory. Right click on the options.ini file and choose "Edit."
Look for the "FirewallPortOverride" entry. If you don’t see this entry, add it as a new line. Then assign the port you want to use to the port override entry. After making this change, this entry should look like:
FirewallPortOverride = XXXX
Where XXXX is the port number you have chosen. You will need to open the chosen port in your firewall for communication with players external to your firewall or NAT device. If you use the port override feature, the port you have chosen can not be masqueraded by a NAT device.
Beste is gewoon DMZ instellen op uw lan ip, dan gaat alles perfect
