If you are running a standalone server, locate the server-settings.json file. Change "verify_user_identity": true to .

This is the most stable method. By creating a virtual local network, the game thinks you are in the same room.

If you're a legitimate game owner, you can use the official multiplayer feature:

:

In the game's config.ini file, ensure verify-user-identity is set to false . This allows players without official accounts to join the server.