[SOLVED] Fatal error: Uncaught Error: Call to undefined function us_amp() – Zephyr Theme

Andrei Iordache

Andrei Iordache

WordPress Developer

­čÜÇ I Help People Get Found Online | WordPress Development, Core Web Vitals, Security&Maintenance

[SOLVED] Fatal error: Uncaught Error: Call to undefined function us_amp() – Zephyr Theme


Today, while I was updating the Zephyr theme for one of my clients from Zephyr 7.10 to Zephyr 7.11, I got this fatal error:

Fatal error
: Uncaught Error: Call to undefined function us_amp() in \wp-content\themes\Zephyr\common\functions\menu.php:104 Stack trace:
#0 \wp-includes\class-wp-walker.php(144): US_Walker_Nav_Menu->start_el('<li id="menu-it...', Object(WP_Post), 0, Object(stdClass))
#1 \wp-includes\class-wp-walker.php(244): Walker->display_element(Object(WP_Post), Array, 0, 0, Array, '<li id="menu-it...')
#2 \wp-includes\nav-menu-template.php(608): Walker->walk(Array, 0, Object(stdClass))
#3 \wp-includes\nav-menu-template.php(228): walk_nav_menu_tree(Array, 0, Object(stdClass))
#4 \wp-content\plugins\us-core\templates\elements\menu.php(80): wp_nav_menu(Object(stdClass))
#5 \wp-content\plugins\us-core\functions\helpers.php(130): include('G:\\XAMPP\\htdocs...')
#6 \wp-content\plugins\us-core\functions\header.php(232): us_load_template('templates/eleme...', Array)
#7 \wp-c in \wp-content\themes\Zephyr\common\functions\menu.php on line 104

There has been a critical error on your website.

Learn more about debugging in …

As you already know, most of the time I backup everything. But, even that, the feeling when you discover any kind of error, after working some hours on a project, is … indescribable.

How to solve this error

Well, to solve this fatal error, it’s as simple as it sounds: Update the UpSolution Core plugin. If it’s not showing as “To be updated” in your WordPress Admin Dashboard, than you must click on “Check again” button, from the “Updates” page.

Don’t forget: Anytime you update something on your website, create a backup before! Beside the fact that you should update your website on a regular basis, even if you don’t update/change content often, do a backup on each new plugin or theme added, or even plugin or theme update.

You never know…

All the best!


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