It seems that several template plugins are causing these kind of issues (Astra Starter templates, Smart Templates, etc.) If you have one of these installed, try to deactivate them and then update all the plugins, including the template ones. Once updated, you can safely re-active such plugins. Hope it helps.
Problems with the navigation menu
Add this to your header.php file. if(!is_user_logged_in()) { wp_die(‘This site is currently undergoing maintenance.’); } You can replace This site is currently undergoing maintenance. with whatever message you want to show.
Based on Bainternet’s answer to this question: Save Theme Options (options.php) From The Frontend The key is to know the name of the plugin option to Enable/Disable the Maintenance Mode. In this example, it’s named: my_maintenance_mode <?php if ( isset($_POST[‘mmode’]) && isset($_POST[‘action’]) && $_POST[‘action’] == “update_mmode” ) { if ( wp_verify_nonce( $_POST[‘theme_front_end’], ‘update-options’ ) ) … Read more
Use the hook template_redirect instead – this will ensure it only runs on the front-end of your site, and not for the admin, login, registration or signup pages. function wpse_159552_maintenance() { if ( ! is_front_page() ) { wp_redirect( home_url() ); exit; } include ‘maintenance/index.html’; exit; } add_action( ‘template_redirect’, ‘wpse_159552_maintenance’ );
I didn’t find an answer to above solution but I have something that works well enough for now. Put other pages I need to link to (“thank you” & “privacy”) is a folder inside the root name “n.” The end result are links that are good enough and not confusing to end users.
A SINGLE Post Giving an “Under Maintenance” Message
I guess, something wrong happened during WordPress or an active plugin or the active theme update. Maybe connection loss or interruption. Have a look at WordPress root directory. If the (hidden) file named .maintenance exists, then safely remove it. It’s the temporary file used by WordPress for few minutes until the update process is finished. … Read more
you can try WP Maintenance Mode plugin also check this link https://www.sourcewp.com/best-wordpress-maintenance-mode-plugins/
How to programmatically put wordpress in maintenance mode