Fatal error: Uncaught Error: Interface "Symfony\Component\HttpFoundation\Session\Flash\FlashBagInterface" not found in I:\www\frameworks\Symfony\doctrine\vendor\symfony\http-foundation\Session\Flash\AutoExpireFlashBag.php:19 Stack trace: #0 {main} thrown in I:\www\frameworks\Symfony\doctrine\vendor\symfony\http-foundation\Session\Flash\AutoExpireFlashBag.php on line 19