Fatal error: Uncaught Error: Class "Symfony\Component\DependencyInjection\ParameterBag\ParameterBag" not found in I:\www\frameworks\Symfony\doctrine\vendor\symfony\dependency-injection\ParameterBag\FrozenParameterBag.php:21 Stack trace: #0 {main} thrown in I:\www\frameworks\Symfony\doctrine\vendor\symfony\dependency-injection\ParameterBag\FrozenParameterBag.php on line 21