LAN games cannot be joined: the host will make the room, open the correct port, and send the correct mDNS packets, but it will not respond to the joining client’s packets
Finally fixed after release. Blizzard, start regarding my posts with more attention if you don’t want to brick the game 
this looks like my field. many older games only supports ip version 4, which is active alongside version 6. in order for older games to work on lan, you need to disable ip version 6 in your windows control panel or mac os finder.
This would not be correct as the game very much establishes a connection and sends the join packet successfully AND the host is listening on the correct port (16000) on 0.0.0.0 (note the IPv4 address being in use), but I have decided to indulge you and disable IPv6 on all of my network interfaces to confirm this is not the case.
Of course, it wasn’t the case.
i tried to help you and you trolled me back? i will ignore you from now on.
I am not trolling, and this is a bug report forum, not a tech support forum. I am writing how it is, this isn’t caused by IPv4 but by an issue with the client newly introduced in 1.33 (which by the way means this isn’t an old game as you mentioned). I also am not sure why you think that was trolling. This is an actual report of broken hosting functionality as the host won’t respond to the join packet.
Still active on 19089