Fatal error: Uncaught Error: Class 'Symfony\Component\EventDispatcher\Event' not found in /home/optinadmin/rfl.optin.co.nz/concrete/src/File/Event/FileVersion.php:7 Stack trace: #0 {main} thrown in /home/optinadmin/rfl.optin.co.nz/concrete/src/File/Event/FileVersion.php on line 7