Fatal error: Uncaught Error: Interface 'Symfony\Component\Mime\Header\HeaderInterface' not found in /var/www/alldocs/home/rprather/TIWebsite/simplesamlphp_idp/vendor/symfony/mime/Header/AbstractHeader.php:21 Stack trace: #0 {main} thrown in /var/www/alldocs/home/rprather/TIWebsite/simplesamlphp_idp/vendor/symfony/mime/Header/AbstractHeader.php on line 21