Warning: require_once(/home/httpd/vhosts/grobetpub.ch/grobetpub21/vendor/autoload.php): Failed to open stream: No such file or directory in /home/httpd/vhosts/grobetpub.ch/grobetpub21/wp-config.php on line 9

Fatal error: Uncaught Error: Failed opening required '/home/httpd/vhosts/grobetpub.ch/grobetpub21/vendor/autoload.php' (include_path='.:/usr/share/pear:/usr/share/php') in /home/httpd/vhosts/grobetpub.ch/grobetpub21/wp-config.php:9
Stack trace:
#0 /home/httpd/vhosts/grobetpub.ch/grobetpub21/wp/wp-load.php(55): require_once()
#1 /home/httpd/vhosts/grobetpub.ch/grobetpub21/wp/wp-blog-header.php(13): require_once('/home/httpd/vho...')
#2 /home/httpd/vhosts/grobetpub.ch/grobetpub21/index.php(5): require('/home/httpd/vho...')
#3 {main}
  thrown in /home/httpd/vhosts/grobetpub.ch/grobetpub21/wp-config.php on line 9