Fatal error: Uncaught Error: Call to undefined method WP_Rewrite::add_rewrite_tag() in /var/sites/memsensors.com/wp-includes/rewrite.php:172 Stack trace: #0 /var/sites/memsensors.com/wp-includes/class-wp-taxonomy.php(405): add_rewrite_tag('%category%', '(.+?)', 'category_name=') #1 /var/sites/memsensors.com/wp-includes/taxonomy.php(385): WP_Taxonomy->add_rewrite_rules() #2 /var/sites/memsensors.com/wp-includes/taxonomy.php(72): register_taxonomy('category', 'post', Array) #3 /var/sites/memsensors.com/wp-includes/class-wp-hook.php(298): create_initial_taxonomies('') #4 /var/sites/memsensors.com/wp-includes/class-wp-hook.php(323): WP_Hook->apply_filters(NULL, Array) #5 /var/sites/memsensors.com/wp-includes/plugin.php(453): WP_Hook->do_action(Array) #6 /var/sites/memsensors.com/wp-settings.php(448): do_action('init') #7 /var/sites/memsensors.com/wp-config.php(88): require_once('/var/sites/mems...') #8 /var/sites/memsensors.com/wp-load.php(37): require_once('/var/sites/mems...') #9 /var/sites/memsensors.com/wp-blog-header.php in /var/sites/memsensors.com/wp-includes/rewrite.php on line 172