When my brother and a friend try to play brood war online, it simply does not work.
First of all, the only way we can get into the same game is if we all join a different game (I guess it sets the latencies the same or something).
At this point we can then host, and we can all join the game, but either one of us cannot dowload the map (it gets stuck) or if it does somehow download, it counts down and we still remain at the screen where we then all have to alt + f4 and rejoin b.net and try again.
My brother and I both run off of the same router. The thing that doesn't make sense is that when my buddy comes over on his laptop, me and him are able to play sc perfectly fine on b.net (if it is just us 2).
This same problem happens with my brothers friend. Him and his brother can play with eachother on b.net, but if they try to play with another person, they aren't able to play.
Unfortunately, the game is not designed for several PCs sharing the same internet connection.
There is a non-supported way, though, which may work out for you. It will require you to modify the Windows Registry. If you are not familiar with editing the registry, ask someone for help.
On one computer of your choice click Start, Run..., type "regedit" and press Enter.
Go to HKEY_CURRENT_USER\Software\Battle.net and click on "Configuration". On the right half of the window do a right-click and create a new DWORD value. Call it "Game Data Port".
Then right-click on the newly created value and select "Modify".
In the new window, click on Decimal (not Hexadecimal) and enter 6113 as value.
Apply the settings, then close the registry again.
This computer will now use port 6113 on Battle.net (applies to StarCraft and maybe to Diablo II as well, but definitely not to Warcraft III).
Repeat the procedure for any additional computers that may be behind the router, but use a different port value then (6114, 6115, 6116, ...). Keep in mind that each computer will have to have a different port value assigned.
The default port value is 6112, so one computer will use this port by default, which is perfectly fine (since you will not need to modify anything here! :) ).
In addition, please make sure that ports 6112-6112 and 6113-6113 TCP/UDP are forwarded ("opened") on your router for the correct computer and/or firewall. You can learn how to do so here:
If that fails, set your ports back to 6112 and try the steps here:
DISCLAIMER: The guide located at the above link is not supported by us, Blizzard, your router manufacturer, or anybody for that matter. In fact, it is highly frowned upon and will void any warranty you may have. We are not responsible for any damage caused by following the steps in the above link. Though, most router manufacturers aren't going to check if you SSH'd into your router and messed with the firmware.
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