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Most Minecraft server problems have a quick fix. Find your problem below and follow the steps. If you’re stuck, the Logs page usually tells you why.

Difficulty

Beginner

Time

5 minutes

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Read the logs first

Open your server and click Logs in the sidebar. It looks in the main folder, logs and crash-reports. Click First error or the Error and Fatal filters to jump to the problem. Copy for support copies the error with passwords, keys and addresses removed. See how to read server logs. To send us the live console, click Share log on the Console page and paste the link into a ticket.

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Common problems

The console shows something like You need to agree to the EULA in order to run the server. Minecraft won’t run until you accept the Minecraft EULA.
  1. Read the EULA.
  2. Open Files and click eula.txt.
  3. Change eula=false to eula=true and click Save Content.
  4. Start the server.
You can also switch on Accept EULA the next time you use Version Changer or Modpacks.
  1. Check the server is Online and the console shows Done (…)! For help, type "help".
  2. Copy the address from the panel and paste it into Server Address in Minecraft, including the port (for example 203.0.113.10:25565).
  3. Make sure you’re using Minecraft: Java Edition. Bedrock players need Geyser.
  4. If the whitelist is on, check you’re on it (Players > Whitelisted).
  5. Still failing? Check our server status page and open a ticket.
Your game version and the server’s version don’t match.
  • Change your launcher to the server’s version. Version Changer shows it at the top (Currently installed: …).
  • Or change the server’s version. See change your version.
  • Or let several versions join with ViaVersion. See popular setups.
The server or a plugin needs a newer Java version than the one selected.
  1. Click Startup.
  2. Under Docker Image, pick the Java version your Minecraft version needs (for example Java 25 for 26.x, Java 21 for 1.20.5 to 1.21.11).
  3. Restart the server.
See the Java version table.
  1. Open Logs and click First error. The error usually names the plugin or mod.
  2. Go to Plugins or Mods > Installed and switch off its toggle (or delete it).
  3. Restart the server.
  4. Check the plugin or mod supports your exact Minecraft version and loader, and that its dependencies are installed.
If you can’t tell which one it is, disable the ones you added most recently, one at a time. Or restore the backup you made before the change from Backups.
Signs: java.lang.OutOfMemoryError, the server stops on its own, or Memory sits at the limit.
  1. Lower View distance in Server Properties (try 6–8).
  2. Pre-generate the world with Chunky instead of letting players explore new land.
  3. Remove plugins or mods you don’t use.
  4. Run spark heapsummary to see what uses the memory.
See performance. If your server simply needs more memory, you can upgrade your plan in the client area.
The world is usually still there. A different server type may look for a different folder.
  1. Click Worlds > Installed and check which world is Active. Click Set active on your old world and restart.
  2. If you used Delete Server Files, restore the backup you made before the change from Backups.
  3. Moving from a single-player or Vanilla world to Paper: Paper stores the Nether and End in world_nether and world_the_end. See worlds.
Never open a world in an older version than it was last played on. It can corrupt the world.
  • With Allow cracked players on, player UUIDs change. Ops, whitelist entries, bans and plugin data were saved under the old UUIDs. Add operators and whitelist entries again on the Players page.
  • If the whitelist is on, add everyone again after switching.
  • Switched it off again? Players without a paid account can no longer join.
See allow cracked players.
The player’s mods don’t match the server’s.
  • Players need the same modpack and the same pack version as the server. Tell them which version you installed.
  • For single mods, content mods must be on both the server and every player’s game, with matching versions.
  • Client-only mods (minimaps, shaders) belong only on the player’s game. Remove them from the server if you added them by hand.
The server couldn’t confirm the player’s account with Mojang.
  1. The player restarts the Minecraft launcher and signs in again.
  2. They check that they’re using an official, paid copy of Minecraft: Java Edition.
  3. If many players see it at once, Mojang’s login servers may be having problems. Wait and try again.
Don’t switch on Allow cracked players just to fix this. It removes account checks for everyone.
Run spark tps to check. Below 20 TPS means the server can’t keep up. Follow performance and use spark profiler to find the cause.

Minecraft FAQ

Quick answers to common questions.

Server logs

Find errors fast.

Backups

Undo a change that broke your server.

Performance

Fix lag and memory problems.

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Need Extra Help?

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Last Updated: October 2026