On Thursday, 2021-02-11, a user submitted an array job with an email address specified. Our computer then sent an email to him when one of the many hundreds of jobs started and when it finished. His e-mail server only allowed him to receive 500 emails per day, so after he had reached that limit an “Undelivered Mail” message was sent to us at support, twice for each of his hundreds of jobs. Each of these “Undelivered Mail” e-mails created a new case in our support system. The user did, in principle, nothing wrong, but as a result our support system was completely shut down. Until we find a permanent solution for this problem, as a temporary fix we have now disabled the email service.