If the server does not work and you need to preserve an existing world, stop and open a support ticket. For a new server whose world does not need to be retained, you can perform a clean reinstall:
- Stop the server.
- Back up any files you may need.
- Reinstall the server and do not start it yet.
- Configure the required values in SpaceEngineers-Dedicated.cfg and click Save and Close.
- Start the server once so that it creates the world and secondary configuration.
- To install modifications, stop the server again.
- Install the modifications and start the server.
After a world has been created, some settings exist in more than one configuration file and may need to be changed in the world-specific configuration as well.