My server won't start or keeps crashing — what do I do?
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When a server won't start or keeps crashing, the answer is almost always sitting in the Console — the last lines before it stopped usually name the exact cause. Here's how to read them and address the most common problems.
First, read the Console
Open the Console and scroll to the last lines before the server stopped. The error message typically points straight at the cause.
Common causes and fixes
- Wrong Java version — set the correct version on the Settings page (newer Minecraft needs Java 17 or 21).
- A broken plugin or mod — remove the one you added most recently.
- A corrupted world — restore a backup from the Backups page or re-upload a known-good copy of the world via Files/SFTP, or open a ticket for help.
- Out of RAM — check the RAM buffer and upgrade if needed.
- Xms above Xmx — fix the RAM variables on the Settings page; a minimum above the maximum crashes instantly.
Steps to recover
- Read the Console error.
- Apply the matching fix above.
- Press Start and watch it boot.
Tip: Use the Console's "Share logs via mclo.gs" button and open a ticket — our team will read the exact error with you.
Frequently asked questions
It crashes instantly with no clear log — why? Check the RAM variables on the Settings page. Xms set above Xmx crashes the server immediately. Then share the log via mclo.gs.
How do I know which plugin or mod broke it? The most recent addition is the prime suspect. Remove it, start, and see if the server is stable.
More in Crashes, Startup Failures & Errors
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- My server restarts on its own / kicks everyone / rolls back periodically — why?
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- My server crashed right after I added a mod or plugin — how do I identify and fix it?