Fatal error: Uncaught Error: Class "Symfony\Bundle\FrameworkBundle\Command\ContainerAwareCommand" not found in C:\xampp\htdocs\electronica\vendor\symfony\assetic-bundle\Command\AbstractCommand.php:21 Stack trace: #0 {main} thrown in C:\xampp\htdocs\electronica\vendor\symfony\assetic-bundle\Command\AbstractCommand.php on line 21