Hello,

Is it possible to play Warcraft II via Battle.net (login through the GOG client) with two player accounts and corresponding licenses in the same WLAN? I want to play Warcraft II against my brother at home, specifically in the same WLAN.

Here’s what I have already tried:

I have purchased two licenses of Warcraft II, and both work correctly. I can log in to Battle.net with both profiles and create multiplayer games.
On both Macs where Warcraft II and GOG are installed (in Parallels Desktop mode), I can log in with both profiles and access the Battle.net platform.
When I log in to Battle.net on one of the two Macs connected to the same WLAN with one of the profiles, the second Mac with the other profile cannot access the platform. The error message states: “Your internet connection is either very poor or does not handle UDP packets over port 6112. You can chat but cannot play. Contact your internet service provider or system administrator for help opening the port.”
I have also tried using a second network on my router with one of the Macs, but that didn’t work (the same error message appeared).
Connecting one of the Macs to my mobile hotspot and using the 5G network doesn’t work either. I can’t even access the platform.
It’s not a general login problem as the router allows the required ports. The question is whether only port 6112 is used in general and if it is locked by the first computer in a network, preventing the second computer from logging in through this port. Alternatively, can the second computer be configured to use a different port like 6113, allowing both computers to log in and play against each other in the same network?

How can I solve this problem? Thank you very much for your response. Best regards, BT19

First. This error messages can appear time to time. Exit to initial menu screen and trying again work.
Alternatively Bnet not needed for LAN or virtual LAN (GameRanger or RadminVPN) - alternate to it are IPX IP connection (game come with ipx wrapper).

Cant say more. I saw such threads there is random issues connect to Bnet from same IP. Old classic and new one. I doubt Blizzard support can be useful. And didnt saw any solutions.
I doubt router settings can solve that. There is strict options for ports and not. Make issues for both local machines or for no one.
So looks like Blizzard issue. Especially knowing their strict IP policy for nowadays Bnet accounts/clients. Account can be blocked temporary if multiple IPs used as "security" feature.

So i can suggest only alternatives of IPX type or unofficial War2ru server. You can add its gateway to exist one and play from GOG version. They make it compatible next to GOG release (initially server require own modified client now any) so you always can try switch to official Bnet again, no game files alternate.