Fatal error: Uncaught Error: Class 'Drupal\Core\Session\AccountInterface' not found in /www/htdocs/w00aa07a/drupal8/core/includes/bootstrap.inc:83 Stack trace: #0 /www/htdocs/w00aa07a/drupal8/core/lib/Drupal/Core/DrupalKernel.php(1004): require_once() #1 /www/htdocs/w00aa07a/drupal8/core/lib/Drupal/Core/DrupalKernel.php(680): Drupal\Core\DrupalKernel::bootEnvironment() #2 /www/htdocs/w00aa07a/drupal8/index.php(61): Drupal\Core\DrupalKernel->handle(Object(Symfony\Component\HttpFoundation\Request)) #3 {main} thrown in /www/htdocs/w00aa07a/drupal8/core/includes/bootstrap.inc on line 83