"Failed to Synchronize registry data from server, closing connection" when joining a serve

  • Make sure that the EXACT same mods installed on both your PC and the server. It is not enough to simply have the same mods installed, they must also be installed in the exact same version. Likewise, the version of the mod loader (Fabric/Forge) must be identical.

    If you use a Modpack make sure you're running the same version as the server.