Most routers (even home routers) have a feature known as port forwarding; you set the ports for Halo to forward to your 192 based server. The net result is that external users are routed to your server by using an external IP address and don't know that this is happening.
For example, if a game or an application uses port 5000 to communicate with the server, set port 5000 to the 192.168 address of your server. If your external IP address for the router is (for example) 31.44.55.66, then users can get to your server by using the 31 address, but packets for the game will be routed to your 192.168 server which is internal.
hi
You have to create your own LAN/Internet server in the Multiplayer menu.
It means you dont have a secure connection to the internet and halo 3 server can locate it. you need a better provider
Product key
Did you set it to local? Or maybe invite only. Try making it open, or invite only. Then go to your friends list and invite them.
halo 2 was
unless you using some privately owned server there is no way.
probably because your computer is to old to handle online play or the halo may have a virus on it, update your computer to new software
Yes, Halo 3 can be played in local co-op campaign and in local and online PvP multiplayer.
Yes
Press start on the main menu
Halo CE doesn't have internet capability, unless you have a patch for it. You can only talk on multiplayer if it's local. In Halo 2, that's fixed though.