Skip to main content
Basic LAN multiplayer functionality is available on the Windows build, allowing you to play Minecraft Legacy Console Edition with friends on your local network. The multiplayer implementation is based on LCEMP.

​
How it works

When you host a multiplayer world, the game automatically advertises it on your local network. Other players running the game on the same network can discover your session from the in-game Join Game menu without needing to manually enter IP addresses.
LAN multiplayer uses automatic network discovery, so you don’t need to configure IP addresses manually. Just host a world and have your friends check the Join Game menu.

​
Network ports

The multiplayer implementation uses two network ports:

TCP port 25565

Used for game connections and gameplay traffic

UDP port 25566

Used for LAN discovery and session advertisement

​
Port configuration

If you’re experiencing connection issues, ensure these ports are not blocked by your firewall:
  • TCP 25565 - This is the default Minecraft port used for game connections
  • UDP 25566 - This port is used for broadcasting and discovering games on the local network
The game uses the standard Minecraft port (25565) for connections. If you have other Minecraft servers running on the same machine, you may experience port conflicts.

​
Hosting a game

To host a multiplayer session:
  1. Launch the game and load a world
  2. Ensure multiplayer is enabled for the world
  3. The game will automatically advertise the session on your local network
  4. Other players on the same LAN can now discover your game
When hosting a game, make sure your Windows Firewall allows the game through both private and public networks if you’re playing on a public network.

​
Joining a game

To join a LAN multiplayer session:
  1. Launch the game on a device connected to the same network
  2. Navigate to the Join Game menu from the main screen
  3. Available games on your LAN will appear automatically
  4. Select the game you want to join and connect
The game uses UDP broadcasting on port 25566 to discover available sessions, so you don’t need to manually enter server addresses.

​
Custom username

You can override your in-game username by creating a username.txt file in the same directory as the game executable.

​
Setting a custom username

  1. Navigate to your game installation directory (where the .exe file is located)
  2. Create a new text file named username.txt
  3. Enter your desired username on the first line
  4. Save the file
  5. Launch the game
The implementation reads the username from username.txt at startup (see Windows64_Minecraft.cpp:778). If the file doesn’t exist or is empty, the game falls back to your Windows username.
Usernames are limited to 16 characters. Any characters beyond this limit will be truncated.

​
Example username.txt

MinecraftPlayer
The game will trim any trailing whitespace, newlines, or carriage returns from the username.

​
Troubleshooting

​
Games not appearing in the join menu

If you can’t see available games:
  • Verify all devices are on the same local network
  • Check that UDP port 25566 is not blocked by firewalls
  • Ensure the host has successfully loaded a multiplayer-enabled world
  • Try temporarily disabling Windows Firewall to test connectivity

​
Connection failed errors

If you can see a game but can’t connect:
  • Verify TCP port 25565 is not blocked by firewalls
  • Check that no other applications are using port 25565
  • Ensure the host’s game is still running and hasn’t crashed
  • Verify both players are running compatible versions of the game

​
Username not changing

If your custom username isn’t working:
  • Verify username.txt is in the same directory as the game executable
  • Check that the file is named exactly username.txt (not username.txt.txt)
  • Ensure there are no extra spaces or special characters in the filename
  • Restart the game after creating or modifying the file

​
Technical details

The multiplayer implementation includes:
  • Automatic session advertising - When hosting, the game broadcasts session information via UDP on port 25566
  • Network discovery - Clients listen for UDP broadcasts to find available games
  • TCP connections - Once a game is discovered, clients connect via TCP on port 25565
  • Username customization - Custom usernames are loaded from username.txt during game initialization
The networking code is primarily located in the GameNetworkManager class and related network components in the source code.

​
Limitations

LAN multiplayer is currently only supported on Windows builds. The feature requires proper network stack implementation for each platform.
  • Multiplayer is limited to LAN (local area network) connections
  • No internet/online multiplayer support
  • Platform-specific network implementations are not available for other platforms
  • The feature is based on LCEMP and may have compatibility limitations

Build docs developers (and LLMs) love

Get started for freeTalk to us