Your Rust server will not start without an RCON password

If your Rust server stops right after you start it and the Console shows an error about a string of zero length, the RCON Password is empty. Rust will not start without one, and the error does not mention RCON. Set a password and start again.

Fix it

1. Open your server in the panel, click the Settings tab, then Game Settings.
2. Find RCON Password. If it is empty, type a password. Use letters, numbers, dots, dashes and underscores, up to 64 characters. Choose one of your own and keep it to yourself.
3. Click outside the field. The panel saves it.
4. Click Start at the top of the page.

Why it happens

While RCON Password is empty, the Overview page shows a card, Your server needs one more thing, with a field for it marked Required: you can fill it in there and click Save instead. Rust needs a password to start its remote console, and it fails while writing its own startup line to the log, which is why the error looks unrelated.

Good to know

• The panel's own Console works without the password. Only outside tools need it: How to connect your own RCON tool to your Rust server.
• If you change the password later, restart the server so it uses the new one. The Active players card, Bans and Admins use it too.
• Other reasons a server does not start: How to fix a server that will not start.