Most problems with a Space Engineers server come down to a few causes. Start with the one that matches what you see.
Players cannot join after a Space Engineers update
Why: Their game is newer than the server because Auto Update is off, or the server has not been restarted since the update.
Fix: Turn Auto Update on and restart the server so it installs the newest build.
Workshop mods fail to load
Why: Enable Experimental Mode is off, and most Workshop mods depend on it.
Fix: Turn Enable Experimental Mode on and restart the server.
The server takes a long time to start after changing mods
Why: The server downloads each Workshop mod on the first start after the list changes.
Fix: Wait for it to finish and do not restart it mid-download. Later starts are faster.
Builds are lost after a restart
Why: Enable Saving is off, so the world is not written to disk.
Fix: Turn Enable Saving on, and keep Auto Save Interval at a value you are comfortable losing.
Programmable blocks accept scripts but nothing runs
Why: Enable In-Game Scripts is off.
Fix: Turn Enable In-Game Scripts on and restart the server.
Direct Connect fails when you type a domain name
Why: Direct Connect in the game has had problems with host names; it works reliably with an IP address plus port.
Fix: Use address:port exactly as shown on the Overview page, and if it still fails try the numeric IP with the port.
Admin rights do not apply after editing the config file
Why: The admin list is only read when the server starts, or the ID was entered outside the Administrators section.
Fix: Check the SteamID64 is inside the Administrators section, save, and restart the server.
Still stuck?
Open a ticket in the category that fits and include the last 50 to 100 lines of the console. See How to open a support ticket and How to fix a server that will not start.
