On 2020-08-30 21:55 BST, Wietse Venema wrote: > An SMTP client in the pickup daemon? How shall the pickup daemon send > a non-delivery notification to the sender?
It looks like we're one objection down! Can I make it two... The pickup daemon doesn't, the mail goes into the hold queue. It's then for the postmaster to check what's going on. If the mail's from-address is forged, which is my concern in this thread, then it's better that no non-delivery notification is attempted. Thank you for your attention to my question, this is more than I had expected. -- Nick