[phpBB Debug] PHP Warning: in file [ROOT]/vendor/composer/ClassLoader.php on line 269: include([ROOT]/vendor/symfony/http-kernel/Symfony/Component/HttpKernel/DependencyInjection/Extension.php): failed to open stream: No such file or directory
[phpBB Debug] PHP Warning: in file [ROOT]/vendor/composer/ClassLoader.php on line 269: include(): Failed opening '[ROOT]/vendor/symfony/http-kernel/Symfony/Component/HttpKernel/DependencyInjection/Extension.php' for inclusion (include_path='.:/opt/php5.6/lib/php')

Fatal error: Class 'Symfony\Component\HttpKernel\DependencyInjection\Extension' not found in /home/clients/677a9d1211c4a8bde84fc55e6a4e57f4/web/phpbb/di/extension/core.php on line 25