CoreX Hosting

Failed to bind to port or unable to access jarfile

Errors "Failed to bind to port" or "Unable to access jarfile".

The port in server.properties must be the one the panel assigned, and the jar name in Startup must match a file that exists.

Before you start: Access to Files and Startup.

Step by step

  1. For "Failed to bind": open server.properties and set server-port to the port shown in the panel (and server-ip empty). Save and start.
  2. Do not run two servers in one (for example a plugin trying to open the game port).
  3. For "Unable to access jarfile": open Versions and reinstall the version; it downloads the jar again.
  4. If you use a custom jar, upload it to the root and set the jar file name in Startup exactly (capitals matter).
  5. Start the server and watch the console until it says Done.
  6. If a plugin opens its own web port (maps, voice chat), give it a different port from Network, never the game port.

Check it worked: The server starts without the error.

Why it happens: A changed server-port, or a renamed/deleted server jar.

More guides on Crashes, startup failures, and errors: