My server won't start — how to diagnose it
A calm, step-by-step way to work out why a server won't boot: read the console, find the first error, and match it to the usual causes.
A server that won't start is almost always telling you exactly why — in the Console. The trick is knowing where to look and how to read the first real error. This guide gives you a calm, repeatable process that works for any game.
1. Read the console from the top
- Open your server and go to the Console tab.
- Restart the server so you get a fresh boot log.
- Read from the top down, not the bottom. The first error or exception is usually the real cause; everything after it is often knock-on noise.
Look for the first line containing ERROR, FATAL, Exception, Caused by:, or a stack trace. Copy that line — it's your best clue and the most useful thing to include in a support ticket.
2. Match it to a common cause
| What you see | Likely cause | Fix |
|---|---|---|
| Server stops right after "starting", no clear error | Out of memory, or a hang — check RAM usage | Upgrade plan, or see the mod-conflict guide for modded servers |
Address already in use / port bind failure |
Wrong port in config vs your allocation | Match the config port to the panel's allocation |
UnsupportedClassVersionError / "requires Java X" |
Wrong Java version | Change the Java image on the Startup tab |
OutOfMemoryError |
Not enough RAM for your plugins/mods/world | Upgrade to a bigger plan |
Failed to load a specific file / EOFException |
Corrupt world or config file | Restore a backup |
| EULA / "you need to agree" | Licence not accepted | Accept it in the panel or set eula=true |
3. If it's config-related, fix and retry
Most start failures on a healthy server are a single bad setting — a typo in a config file, a wrong port, or a missing value. Edit the file in the File Manager, save, and restart. Change one thing at a time so you know what fixed it.
4. Roll back if something got corrupted
If the server was fine until a recent change (a plugin, a config edit, a world import) and now won't boot, the fastest fix is often to restore a recent backup from the Backups tab. See Backing up your server.
5. Reinstall as a last resort
If nothing else works and you don't need the current files, Settings → Reinstall re-runs the install script and gives you a clean base. This can overwrite files, so take a backup first if there's anything you want to keep.
When to open a ticket
If the first error doesn't match anything above, open a support ticket and include:
- The first
ERROR/Caused by:line from the console. - What you changed just before it broke.
- Your game and server type.
We'll read the full log on the node and tell you exactly what's wrong.