This error means the server tried to open its network port and something refused. Almost always the old process from your last session is still running.
What you are seeing
**** FAILED TO BIND TO PORT!Perhaps a server is already running on that port?- The server stops immediately after printing it.
Why it happens
A port can only be held by one process at a time. If the previous run did not shut down cleanly, it is still holding the port when the new one tries to start.
What to do
- Stop the server properly, then start it
Use Stop rather than Restart, wait for the panel to report it as offline, and only then start it again. A restart can begin the new process before the old one has released the port.
- Check
server-portmatches your allocationIn
server.properties,server-porthas to be the port shown in the panel. If you changed it by hand to something that is not yours, the server has no permission to bind it. - If it persists, use the kill button once
That forces the process down and frees the port. Use it only when a normal stop has already failed — it does not let the world save.
The console gets past the binding line and reaches Done.
If you are running a proxy network, each backend needs its own port. Two backends pointed at the same one produce this error on whichever starts second.