Experimental Mode is on by default in the Game and the Server files.
If you do not want the server on the Experimental mode please do the following:
1. Stop your server in the Gamepanel.
2. Look through the latest logs in log viewer and locate the following lines
2019-03-05 03:32:51.095 - Thread: 1 -> Experimental mode: Yes
2019-03-05 03:32:51.096 - Thread: 1 -> Experimental mode reason: ExperimentalMode, MaxPlayers, MaxFloatingObjects, EnableWolfs, EnableSpiders, EnableSubgridDamage
3. Go to File Manger\Instance\Saves\Your Wolrd Name (Pingperfect is default)\Sandbox.sbc
4. In the Sandbox.sbc file you can find a line that looks like this <ExperimentalMode>true</ExperimentalMode>,change true to false
5. Change all the values listed as the Experimental mode reason. For example Experimental mode reason: EnableSpiders means you have Spiders enabled and you need to disable them for experimental mode to be switched off
6. Save the file
7. Start the server.
Looking for a game server host known for brilliant 24/7 customer support and quality hardware?
Try a Pingperfect Space Engineers server today! https://pingperfect.com/gameservers/space-engineers-game-server-hosting-rental.php