Fatal error: Uncaught Error: Class "Sabre\DAV\Auth\Backend\AbstractBasic" not found in /home/tzuovhm/tzuovhm/apps_/federation/lib/DAV/FedAuth.php:15 Stack trace: #0 {main} thrown in /home/tzuovhm/tzuovhm/apps_/federation/lib/DAV/FedAuth.php on line 15