DMARC - gmail.com or is it yahoo.com

[Jack]

On 2016.11.29 09:24, cyg Simple wrote:
> I find this excerpt from cygwin-help a bit confusing.  Notice the
> "yahoo.com" in the "Remote host said:" message.  What's really going  
> on
> here?  Why is yahoo.com doing the authentication for a gmail.com  
> address?
> 
> <excerpt>
> Received: (qmail 130602 invoked for bounce); 17 Nov 2016 10:26:04  
> -0000
> Date: 17 Nov 2016 10:26:04 -0000
> From: MAILER-DAEMON@sourceware.org
> To: cygwin-return-205832-@cygwin.com
> Subject: failure notice
> 
> Hi. This is the qmail-send program at sourceware.org.
> 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.
> 
> <cygsimple@gmail.com>:
> User and password not set, continuing without authentication.
> <cygsimple@gmail.com> 173.194.202.27 failed after I sent the message.
> Remote host said: 550-5.7.1 Unauthenticated email from yahoo.com is  
> not
> accepted due to domain's
> 550-5.7.1 DMARC policy. Please contact the administrator of yahoo.com
> domain if
> 550-5.7.1 this was a legitimate mail. Please visit
> 550-5.7.1  https://support.google.com/mail/answer/2451690 to learn  
> about the
> 550 5.7.1 DMARC initiative. e69si30940847pfk.231 - gsmtp
> </excerpt>
> 
> --
> cyg Simple
I haven't looked at the details of this particular error, but are you  
using an alias'd address?  For example, my return address here is  
@users.sourceforge.net.  However, they only resend mail to that address  
to my real address @frontier.com.  I have validated to frontier.com  
that I really do own the address @sourcegforge.net.  So I send through  
the frontier server with a From: address of sourceforge.

In my case, with a KDE mailing list, when KDE gets a message, they ask  
the domain of the message (sourceforge) about their policy.  Recently,  
they upped the level, and so told KDE to reject any mail appearing to  
be from sourceforge if it didn't actually come from their.  Thus I got  
lots of this type of error.  Someone finally convinced sourceforge that  
didn't make sense, since one of their offerings is aliased email  
addresses, which were then all bouncing.

So, your From: is gmail.  Are you actually sending through a gmail  
server, or through a yahoo server?  (Note yahoo servers handle all  
sorts of other domains, not lease most of the domains used by AT&T as  
an ISP.)

Jack
--
Problem reports:       http://cygwin.com/problems.html
FAQ:                   http://cygwin.com/faq/
Documentation:         http://cygwin.com/docs.html
Unsubscribe info:      http://cygwin.com/ml/#unsubscribe-simple