Separate names with a comma.
Check your game options, tick the option to enable asset mismatch or so and it will not show you the message trying to join.
Such error is pretty much all the times related to your player client mods causing incompatibilities. I would recommend checking...
Hello, you can join our server without one account or password.
If you want a login please check into http://ilovebacons.com/acc to request one.
This is being overhauled because of Port Lux, is not working correctly at this moment.
We do not support spacestation claims in worldbound, hence it is not possible for us to back them up. :/