call_user_func_array() error

Try manually resetting your plugins (no Dashboard access required). If that resolves the issue, reactivate each one individually until you find the cause.

If that does not resolve the issue, access your server via SFTP or FTP, or a file manager in your hosting account’s control panel (consult your hosting provider’s documentation for specifics on these), navigate to /wp-content/themes/ and rename the directory of your currently active theme. This will force the default theme to activate and hopefully rule-out a theme-specific issue (theme functions can interfere like plugins).

I tried doing what you said James, but it didn’t work. ??

Ok, try downloading WordPress again, access your server via SFTP or FTP, or a file manager in your hosting account’s control panel (consult your hosting provider’s documentation for specifics on these), and delete then replace your copies of everything on the server except the wp-config.php file and the /wp-content/ directory with fresh copies from the download. This will effectively replace all of your core files without damaging your content and settings.

Some uploaders tend to be unreliable when overwriting files, so don’t forget to delete the original files before replacing them.

Hi there, I have the exact same issue after an update plus an additional fatal error. It says this when I go to my domain https://www.unicornfly.com.

I am not a programmer and never had such issues before. Can someone exactly tell me what to do? I am afraid to delete anything and re-download wp, as James Huff proposes. How do I exactly save the data before?

“Warning: call_user_func_array() expects parameter 1 to be a valid callback, function ‘wp_maybe_grant_install_languages_cap’ not found or invalid function name in /home/nlk1409/public_html/wp-includes/class-wp-hook.php on line 300

Fatal error: Uncaught Error: Class ‘WP_Widget_Media_Gallery’ not found in /home/nlk1409/public_html/wp-includes/class-wp-widget-factory.php:106 Stack trace: #0 /home/nlk1409/public_html/wp-includes/widgets.php(115): WP_Widget_Factory->register(‘WP_Widget_Media…’) #1 /home/nlk1409/public_html/wp-includes/widgets.php(1619): register_widget(‘WP_Widget_Media…’) #2 /home/nlk1409/public_html/wp-includes/class-wp-hook.php(298): wp_widgets_init(”) #3 /home/nlk1409/public_html/wp-includes/class-wp-hook.php(323): WP_Hook->apply_filters(NULL, Array) #4 /home/nlk1409/public_html/wp-includes/plugin.php(453): WP_Hook->do_action(Array) #5 /home/nlk1409/public_html/wp-settings.php(448): do_action(‘init’) #6 /home/nlk1409/public_html/wp-config.php(101): require_once(‘/home/nlk1409/p…’) #7 /home/nlk1409/public_html/wp-load.php(37): require_once(‘/home/nlk1409/p…’) #8 /home/nlk1409/public_html/wp-admin/admin.php(31): require_once(‘/home/nlk1409/p…’) #9 /home/nlk1409/public_html/wp-admin/plugins.php(10): require_once(‘/home/nlk140 in /home/nlk1409/public_html/wp-includes/class-wp-widget-factory.php on line 106

Thanks a lot in advance.