Fatal error: Uncaught Error: Class 'Yoast\WP\Free\Yoast_Model' not found in /wp-content/plugins/wordpress-seo/migrations/20180515101200_WpYoastIndexableMeta.php:72 Stack trace: #0 /wp-content/plugins/wordpress-seo/migrations/20180515101200_WpYoastIndexableMeta.php(20): WpYoastIndexableMeta->get_table_name() #1 /wp-content/plugins/wordpress-seo/vendor_prefixed/ruckusing/lib/Task/Db/Migrate.php(223): WpYoastIndexableMeta->up() #2 /wp-content/plugins/wordpress-seo/vendor_prefixed/ruckusing/lib/Task/Db/Migrate.php(196): YoastSEO_Vendor\Task_Db_Migrate->run_migrations(Array, 'up', NULL) #3 /wp-content/plugins/wordpress-seo/vendor_prefixed/ruckusing/lib/Task/Db/Migrate.php(114): YoastSEO_Vendor\Task_Db_Migrate->prepare_to_migrate(NULL, 'up') #4 /wp-content/plugins/wordpress-seo/vendor_prefixed/ruckusing/lib/Ruckusing/Task/Manager.php(172): YoastSEO_Vendor\Task_Db_Migrate->execute(Array) #5 /wp-content/plugins/wordpress-seo/src/initializers/migration-runner.php(118): YoastSEO_Vendor\Ruckusing_Task_Manager->execute(Object(Yoast\W in /wp-content/plugins/wordpress-seo/migrations/20180515101200_WpYoastIndexableMeta.php on line 72