MarvinMC Open Versions for game/runtime changes. The offered choices come from the available server archive; not every historical build is necessarily available.
Step by step
- Back up the server and stop it cleanly.
- Select the software type, then the game version.
- Review the automatically recommended Java version. Use the requirements of your exact software or modpack when they differ.
- Confirm any EULA prompt and save. Forge/Fabric installations may require additional installation time.
- Start the server and inspect the beginning of the log for compatibility errors.
Check the result
The overview should show the chosen version. A regular start does not intentionally replace a custom server.jar.
Important
Do not downgrade a world without a compatible backup. Server software, plugins, mods and Java must work together; changing only Java cannot resolve every compatibility error.