Execute the OCC Command to Disable Maintenance Mode

Using the command-line interface (CLI) is the most reliable method to toggle maintenance mode, as it bypasses potential caching issues with the config file.

1. Access your server terminal.
2. Run the following command as the web server user (e.g., www-data): sudo -u www-data php occ config:system:set maintenance --value=false --type=boolean.
3. If the instance remains stuck, run the following to verify the mode status: sudo -u www-data php occ maintenance:mode --off.
4. Confirm the status change by attempting to log in via your web browser.

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