How do I safely edit server.properties (e.g. a missing online-mode line)? — Minecraft

Q: My edit didn't apply — why?

You likely didn't restart, or you added stray spaces (key = value instead of key=value). Fix the spacing and restart.

server.properties is the heart of your server's configuration, so a careful edit here keeps everything running smoothly. Editing it safely is mostly about changing only what you mean to and leaving the rest alone.

The safe way to edit

Edit server.properties in the Files tab, or via SFTP if you prefer a desktop editor. The golden rules:

Change only the value after the =.
Keep the key names exactly as they are.
Don't delete lines you don't understand.
Never put spaces around the =.

If a line like online-mode is missing entirely, you can add it on its own line — for example online-mode=false.

Step-by-step

Open the Files tab and click server.properties to edit it.
Find the key you want to change and edit only the value after =.
If the line doesn't exist, add it on a new line (e.g. online-mode=false).
Save the file.
Restart the server for changes to take effect.

Warning: Deleting server.properties regenerates defaults but does not delete your world. Even so, back up before big edits (download your files via the Files tab or SFTP), and never add spaces around the =.

Frequently asked questions

I deleted server.properties — is my world gone? No. Deleting it only regenerates default settings; your world files are separate and untouched.

My edit didn't apply — why? You likely didn't restart, or you added stray spaces (key = value instead of key=value). Fix the spacing and restart.

How do I back up before editing? Download the file (or your whole server folder) via the Files tab or SFTP. If you need help, open a ticket and staff can assist.