Fatal error: Uncaught Error: Class "GuzzleHttp\Event\AbstractTransferEvent" not found in /users/ms-it/www/oc/lib/composer/guzzlehttp/guzzle/src/Event/EndEvent.php:14 Stack trace: #0 {main} thrown in /users/ms-it/www/oc/lib/composer/guzzlehttp/guzzle/src/Event/EndEvent.php on line 14