Here, we will review the process of enabling maintenance mode on your Joomla 3.x website. This means that you will place your website into offline mode and hide the changes that you make on your website until you fully complete them.
When the maintenance mode is enabled on your website and you are not logged in as administrator, you will see the following message when trying to access your website.
Log in as administrator and navigate to the System tab in the main menu and then Global Configuration.
Edit the following options:
Click the Save & Close button at the top to keep the changes.
The same process is used to disable the Maintenance mode in Joomla 3.x. The only difference is that you need to set the Site Offline option to No in Step 1.