In http://email.plus.net/ you have the ability to create a re-direct to blackhole. This is fine if you only ever receive spam to the email address and you just want it all silently dumped. However it isn't a great solution if there is a chance that there's someone you forgot to notify that you were dropping the email address because you could lose a genuine email as the sender doesn't get a bounce message. Solution: Instead of creating a redirect to blackhole, create a redirect to a totally invalid email address (I use firstname.lastname@example.org - the important thing is that the domain is invalid). Now, if an email is sent to this address Plusnet will bounce it instead of silently dropping it. Example: Some time ago I created a mailbox on my account for bobpullen to test a specific issue. Now it's no longer required I have changed it to a redirect as above. Here's the result when I try sending an email to that address:
from Mail Delivery System MAILER-DAEMON@ptn-ipout02.plus.net to email@example.com date 10 September 2011 09:32 subject Delivery Status Notification (Failure) mailed-by relay.ptn-ipout02.plus.net
The following message to <firstname.lastname@example.org> was undeliverable. The reason for the problem: 5.1.2 - Bad destination host 'DNS Hard Error looking up mailbox.inv (MX): NXDomain' Final-Recipient: rfc822;email@example.com Action: failed Status: 5.0.0 (permanent failure) Diagnostic-Code: smtp; 5.1.2 - Bad destination host 'DNS Hard Error looking up mailbox.inv (MX): NXDomain' (delivery attempts: 0)
---------- Forwarded message ---------- From: Me <firstname.lastname@example.org> To: email@example.com Date: Sat, 10 Sep 2011 09:32:26 +0100 Subject: Test Test email bounce
Note: Although this forces the Plusnet email system to behave as you would expect and bounce emails for which there is no mailbox it does risk increasing back-scatter* and so should only be used with due consideration.
* If a spammer is spoofing someone's email address the spoofed address will get a bounce where with black-holing they receive nothing.