Fatal error: Uncaught Error: Class "Symfony\Component\Config\Loader\FileLoader" not found in D:\Apache24\www\qilu\back-end\vendor\symfony\routing\Loader\YamlFileLoader.php:30 Stack trace: #0 {main} thrown in D:\Apache24\www\qilu\back-end\vendor\symfony\routing\Loader\YamlFileLoader.php on line 30