You’re probably here because something went wrong with your Sponge server. Let’s see if we can figure out what it was, and what to do about it.

Java Is Not Installed On Your Computer

Solution: Get Java. Visit the Installing Java for more information.

Network Connection Failure (or DDoS Attack)

Symptoms: Network connection is very laggy, drops in and out, or absent.

Solutions: Check your connection to the modem or router. See if your browser has similar troubles. You can use a free service like to check your connection speed. Other services running on your computer or local network may the cause. Make sure that you have enabled Port Forwarding on your router. A DDoS attack, while unlikely, will probably completely kill your connectivity, and you should contact your ISP if you believe this to be the case.

Not Enough Free Memory

Symptoms: Server crashes, often accompanied with «Out of Memory» messages.

Solutions: Expand the maximum Perm memory size with the startup argument -XX:MaxPermSize=128. Expand your server heap memory (if possible) with startup arguments eg. -Xms1024M (1GB starting memory) and -Xmx2048M (2GB maximum). Monitor your free memory on the computer and see if there is some locked up in other processes. You may need to kill frozen java processes, or restart your machine. Memory leaks sometimes occur with bugs in plugins, which can take time to isolate.

Still an issue?: If you are still having issues despite the above and cannot increase the Heap Size, check in your Task Manager to see if you are using all available Memory. If you are, the only solution is to add more RAM to your system. If there is still plenty of memory available, you are running 32-bit Java. If you are using 32-bit Java, we recommend an upgrade to 64-bit Java, provided that your Operating System is also 64-bit.

Malformed Config File (eg. Bad Editing)

Symptom: One (or more) plugins refuse to load, or behave in unexpected ways. The server log files will contain messages about unreadable files on startup. The server may crash, and data may be corrupted.

Solution: Stop the server, and check your edited files. Load backup files of any corrupted data. You may need to delete a config file entirely and allow it to regenerate upon server startup.

A Plugin (or Mod) Has Malfunctioned

Symptom: This could be almost anything - whatever your plugins do, plus the X-factor. Commonly the server crashes with a train of error messages in the server log files.

Solution: Stop the server, and check to see nothing has been corrupted. Be sure to check that it isn’t from an incorrectly edited config file (above). Remove suspect plugins and add them again one by one, restarting the server each time. The problem may originate from one plugin that is out of date - check for updates. Plugin conflict may also be the cause, having two incompatible plugins.

Operating System Unstable (eg. Virus Infection)

Symptom: The server keeps crashing or timing out, and other parts of your operating system are also having problems.

Solution: Stop everything. Thoroughly check your system and storage devices for malware and viruses. Good tools for this include AdwCleaner, Junkware Removal Tool, MalwareBytes, and most antivirus ware. Check your server files for corruption after a clean restart of your system. Examine the hardware for damage too if the problems persist - eg. a faulty power supply.

Corrupted Data

Symptom: World files fail to load or cause server to crash when players enter certain chunks. Database corruption.

Solution: Load backup files of corrupted data. Software for repairing damaged worlds is available, and missing regions may be regenerated. Investigate the cause of corruption - was it a malformed plugin, database driver, power failure or something else? Always make sure you make regular backups of important data onto a secure device.

Problem Between Keyboard and Chair

Symptom: Everything was working fine yesterday. It went strange today after I did XYZ …

Solution: SpongeDocs is not large enough to encompass the things people may do that will cause software to fail in unpredictable ways. It is always worth thinking long and hard about what you may have done recently that could have affected the smooth running of your server. A memory card may be loose after dusting, a shortcut may be broken…

There is a Bug in Sponge

Symptom: None of the above apply, and it still doesn’t work as it should.

Solution: Time to get out the big guns. File a report on the SpongeForge or SpongeVanilla issue tracker, remembering to include details of the version of Forge and Sponge you are using, and a link to the relevant server log file.

There is Something Wrong With the Universe

We can’t help you with this one. You’re on your own.