Fatal error: Uncaught Error: Class 'Concrete\Core\Foundation\ConcreteObject' not found in /home/gmcguire/public_html/concrete5/concrete/src/User/PrivateMessage/Mailbox.php:9 Stack trace: #0 {main} thrown in /home/gmcguire/public_html/concrete5/concrete/src/User/PrivateMessage/Mailbox.php on line 9