Fatal error: Uncaught Error: Class "Sabre\DAV\Auth\Plugin" not found in /home/tzuovhm/tzuovhm/apps_/dav/lib/CalDAV/Auth/CustomPrincipalPlugin.php:17 Stack trace: #0 {main} thrown in /home/tzuovhm/tzuovhm/apps_/dav/lib/CalDAV/Auth/CustomPrincipalPlugin.php on line 17