It can happen that in the Cron Jobs the sending of emails is not executed correctly and an error like this appears in the console log:
PHP Warning: fsockopen(): php_network_getaddresses: getaddrinfo failed: Temporary failure in name resolution in /var/www/html/pandora_console/include/swiftmailer/classes/Swift/Transport/StreamBuffer.php on line 233
It seems to be a PHP problem. The solution to this, is to stop the Apache service for a few minutes so that all threads are completely removed and restart Apache with:
/etc/init.d/httpd stop /etc/init.d/httpd start