java.lang.NoSuchMethodError / NoSuchFieldError

What is this error?

The java.lang.NoSuchMethodError and java.lang.NoSuchFieldError are common Java exceptions that occur when your server attempts to run code that expects a specific method or field to exist, but finds a different version or signature instead. In a Minecraft server context, this almost always points to a compatibility conflict between your server software, plugins, or mods.

Common Causes

• Version Mismatch: A plugin or mod is compiled for a different version of the server software (e.g., using a Paper 1.20 plugin on a 1.18 server).
• Dependency Conflicts: Two plugins are trying to use different versions of the same library, causing the server to load the wrong one.
• Outdated Software: Running an older build of Spigot, Paper, or Fabric that lacks the API methods required by your newer plugins.

How to fix it

1. Check your logs

The error message in your console will usually name the specific class or plugin causing the crash. Look for the line immediately following the error; it will often name the plugin responsible for the conflict.

2. Update your plugins and server software

Ensure all your plugins are compatible with your current server version.

On AwakeNode:

• Use the Plugin Installer or Mod Installer to quickly update your files to the latest stable versions.
• Use the Version Changer to ensure your server core (Paper/Fabric/Forge) is up to date.

On other hosts / manually:

• Download the latest versions of your plugins from their official sources (SpigotMC, Modrinth, or GitHub).
• Use your SFTP client to replace the old .jar files in your plugins or mods folder.

3. Identify conflicting plugins

If the error persists, remove your plugins one by one (or in groups) to isolate the culprit. If you have two plugins that perform similar tasks, they may be conflicting over shared dependencies.

4. Contact Support

If you have verified that all plugins are updated and the error persists, there may be an issue with your Java environment or server startup arguments.

On AwakeNode:

• Open a Support ticket. Our team can review your startup flags and ensure your environment is configured correctly for your specific server type.

On other hosts / manually:

• Review your startup script. If you are using custom flags that force specific library versions or Java paths, you may need to revert them to the default settings provided by your host.