#startup

Switch your bot from one language to another with Settings → Change Egg, and change the Node.js, Python or Java version with the Docker Image list in Startup.

In Startup you can change the Docker Image (Java or Node.js version) and variables; the startup command is read-only (ask support for a custom one). Versions picks Java for you.

The Versions tab picks the right Java for you. If a server still needs a specific Java (Java 25 for 26.1+, Java 21 for 1.20.5–1.21.11), choose it in Startup → Docker Image.

This error means the server, or a plugin, tried to use a port it doesn't own. Never change server-port yourself; the panel assigns it. Give plugins their own extra port from the Network tab.

A server that stops right after Start prints the reason in the Console. Usually it's a broken plugin or mod, the EULA, wrong Java after a manual change, or a full disk.