Ports: Dpball runs on port 27910 by default (you can change the port by starting the server with +port <#>.
Forward the port: login on your router, usually at
http://192.168.1.1Find out your local ip, on your taskbar click on Start > Run, or press Ctrl+R and then type "ipconfig" it will tell you your local ip, commonly it will be something like "192.168.1.1xx", now you need to go to your router's port forwarding page, for the starting and the stopping port # use "27910". For the ip, use your local ip, the one you found with ipconfig.
Now to check to see if your server is up: Go to
http://ipchicken.com and copy the IP that it gives you, this is your Internet IP (your Internet IP is your internet connection's IP address, your ip from ipconfig is your local, or "Intranet" IP, it only works within your network), now check this list to see if your Internet IP is on it
http://dpball.com/serverlist.php, if you see your IP on there then it worked.
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Here's some screenshots from my linksys:
DigitalPaintball 1
ยท:[ QI Paintball for Q1/QW ]:.