For those who still wonders, the problem is because the game was created at some point in history where people did have just one network interface. Nowadays, with multiple ethernet interfaces (wired, wifi) plus VPN, plus Hamachi, plus WSL, plus VMWare virtual interfaces, the game doesn't know on which interface to listen. When you start a local LAN TCPIP game, you need to make sure it shows the proper IP, the one on your LAN which normally starts with 192.168.0.xxx

The easy way to fix it is to open ncpa.cpl to manage the network interfaces and disable them all and then start the server. You just have to do this on the server, the client will find it easily.

Normally, when you start the server, the Windows firewall will ask to add a rule for incoming connections. If it doesn't, you just open wf.msc and add an inbound exception for that particular program (hota.exe or homm3.exe).

The hard way would be to modify priorities of interfaces, like the broken link above was supposed to explain. I don't recommand that.

Harder way would be to patch the executable to listen properly :)

Just comment
No, actually back in old days it can be multiple networks. Sometime playeer was able simulate hotseat in a TBS game that do not have hotseat. Its a bit harder nowadays.

if you have some virtual - they propable indeed redirect it.. wait, why probably? Virtual lan networks (radmin hamachi or gaming one GameRanger) is exactly overtake it.

I'm starting to look at this problem for Linux wine (on Ubuntu 22.04)

Some of the suggestions made on this thread (e.g. "switch off all firewalls") aren't very sensible, others use approaches that don't exist in wine or are inordinately difficult (e.g to control network interfaces from ncpa.cpl)

But this guide looks good: https://www.celestialheavens.com/forum/7/16061 it needs port forwarding and DirectPlay so I'll work through this. UPnP needing to switch off would be a deal-breaker for me so hopefully I won't meet that obstacle.

And apparently running wine may be a solution for windows users as well, since wine comes with a non-crippled version of DirectPlay

I've got LAN Multiplayer working now on 2 Ubuntu 22.04 pcs thanks to the guide here:-

[url=https://www.celestialheavens.com/forum/7/16061https://www.celestialheavens.com/forum/7/16061[/b[/url]]

Since those commenters have solved lots of problems by trial and error, this might be a good workaround for Windows users too, if they install wine on a virtualbox

I used PlayOnLinux 4.3.4 to make the wineprefix, with these settings:-
Wine 3.0.3
Windows XP
Winetricks to install: directx9, directplay
Winecfg dll overrides: smackw32.dll, wsock32.dll (I'm pretty sure these weren't actually needed)

I may have replaced sock32.dll with a version from the ipxemu-1.0.4 package (but if so I doubt this mattered)

The old version of wine turned out to necessary for me because on 6.10-staging. installing directplay always caused the game to crash whenever the Host button is pressed - and thus wrecked the entire wineprefix, meaning I kept having to start over. This happened on both ubuntu pcs so I mention it in case it's a bug.

I set up port forwarding for 47264, 2300-2400 on the router, like the guide says, and using the instructions at https://portforward.com/ On my router I just have to log into the router interface and type those port numbers into a box, then a local pc's IP address in the next box, and then that it's for both TCP and UDP.

Being a setting for "virtual servers", I'd have thought this should force a particular PC to act as the Host in the game, but it doesn't seem to, which I guess is because in a LAN game the router never receives any packets on 47264 from the internet - and the game is pointlessly checking that if any HOMM3 packets did come in from the internet, the router would forward them.

Contrary to the guide's strong advice, I found I didn't need to disable UPnP (so far).
I wonder if the port forwarding might not have been needed either - directplay might have been enough but I did that step last because it kept ruining the wineprefixes.

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These are some (warning: possibly distro-specific) commands for opening ports on the pcs

sudo apt-get install iptables-persistent
sudo apt-get install nmap

sudo iptables-save > IPtablesbackup.txt

sudo iptables -A INPUT -p tcp --dport 47624 -j ACCEPT
sudo iptables -A INPUT -p tcp --dport 2300:2400 -j ACCEPT
sudo netfilter-persistent save

sudo ufw allow 47624/udp
sudo ufw allow 47624/tcp
sudo ufw allow 2300:2400/udp
sudo ufw allow 2300:2400/tcp

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This other thread explains how to disable the intro video by editing a registry setting.
With problem wine installs like this we often have to delete wineprefixes and start again - so this may save time

https://www.gog.com/forum/heroes_of_might_and_magic_series/homm3_cant_skip_introduction/page1

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