Re: Postfix based mailing list and yahoo's errors

[Greg Troxel <gdt%lexort.com@localhost>]

Mayuresh <mayuresh%acm.org@localhost> writes:

> I am running a mailing list using postfix aliases.
>
> I find that it works fine with gmail users, but yahoo is rejecting mails
> (note: not marking spam, simply rejecting) with the reject message citing
> the following help URL:
>
> https://help.yahoo.com/kb/postmaster/SLN7253.html?guccounter=1
>
> I am intrigued by their suggestion that goes like this:
>
>     For mailing lists, also known as "listservs," you should change your
>     sending behavior by adding the mailing lists’ address to the "From:"
>     line, rather than the sender’s address.  Also, enter the actual
>     user/sender address into the "Reply-To:" line.

You should be aware that opinions on this differ widely.  Yahoo seems to
be performing cryptographic checks that mail from their domain is not
altered in any way when accepting that mail back for delivery to yahoo.
Mailinglists typically modify messages by adding a subject line tag or a
footer.  These two practices are not compatible.

> On the contrary I have seen some mailing lists putting Reply-To address as
> that of the list leaving From address untouched.

That's an entirely different issue.  That practice is contrary to
standards.

https://www.unicom.com/pw/reply-to-harmful.html
http://marc.merlins.org/netrants/reply-to-still-harmful.html

> I notice netbsd mailing lists are neither altering From field nor adding
> Reply-To. How does it work with yahoo? (I am assuming some yahoo users
> would be there on the list.)

I don't know if it does or doesn't work.  I would say that people from
yahoo having trouble should consider a mail provider that allows them to
subscribe to mailinglists :-)

> I have an smtp_header_check which adds Reply-To as the lists address
> (quite contrary to yahoo's suggestion).

And contrary to IETF standards.  Repent!