Fatal error: Uncaught Error: Class "Sabre\Xml\Element\XmlFragment" not found in /server/www/10.1.1.5/htdocs/vendor/sabre/dav/lib/DAV/Xml/Property/Complex.php:20 Stack trace: #0 {main} thrown in /server/www/10.1.1.5/htdocs/vendor/sabre/dav/lib/DAV/Xml/Property/Complex.php on line 20