On Friday 13 November 2015 22:14:30 Don Armstrong wrote:
> On Fri, 13 Nov 2015, Steve Kleene wrote:
> > Almost five years ago, I became unable to post questions here by e-mail.
> > The
> >
> > e-mail bounces with, for example:
> > > The following message to <debian-user@lists.debian.org> was
> > > undeliverable. The reason for the problem:
> > > 5.1.0 - Unknown address error 550-'5.1.7
> >
> > <prvs=752320ad2=sk...@syrano.acb.uc.edu>: Sender address rejected:
> > undeliverable address: host syrano.acb.uc.edu[129.137.3.161] said: 550
> > 5.1.1 <prvs=752320ad2=sk...@syrano.acb.uc.edu>... User unknown (in reply
> > to RCPT TO comm
> >
> > > --4pO84.596/vqwKa.2j26M/gYqU.DibVXRw
> > > content-type: message/delivery-status
> > >
> > > Reporting-MTA: dns; ucmailmx4.uc.edu
> > >
> > > Final-Recipient: rfc822;debian-user@lists.debian.org
> > > Action: failed
> > > Status: 5.0.0 (permanent failure)
> > > Remote-MTA: dns; [82.195.75.100]
> > > Diagnostic-Code: smtp; 5.1.0 - Unknown address error 550-'5.1.7
> >
> > <prvsu2320ad2=sk...@syrano.acb.uc.edu>: Sender address rejected:
> > undeliverable address: host syrano.acb.uc.edu[129.137.3.161] said: 550
> > 5.1.1 <prvsu2320ad2=sk...@syrano.acb.uc.edu>... User unknown (in re
> >
> > > --4pO84.596/vqwKa.2j26M/gYqU.DibVXRw
> > > content-type: message/rfc822
> >
> > This commenced about the time my employer started prepending a bounce
> > address validation tag ("prvs=752320ad2=" in the above example) to my
> > e-mail address on outgoing mails. This fails with the debian lists but
> > nowhere else. I have circumvented the problem ever since by posting via
> > gmane.org.
>
> This is because you are not supporting sender callback verification; the
> envelope from that you are using needs to be an address which can be
> received. If not, it's not valid.
>
> See https://en.wikipedia.org/wiki/Callback_verification for details
That's the problem, not the solution, Don.
Lisi
