I received this notification when an email I sent didn’t get through.
Hi. This is the qmail-send program at netmail.mail.registeredsite.com. I’m afraid I wasn’t able to deliver your message to the following addresses. This is a permanent error; I’ve given up. Sorry it didn’t work out.
It sounds like one of those Sirius Cybernetics Corporation doors from Hitchhiker’s Guide to the Galaxy.
“I hope you’ve enjoyed having your message rejected by this service.”