On Sunday 29 March 2015 10:43:06 Will Hill wrote:
> I keep getting bounce warnings from this list, apparently because of a
> problem with Yahoo.  The bounce messages say,
>
> "host gmail-smtp-in.l.google.com[74.125.70.26] 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 administrator of
> yahoo.com domain if 550-5.7.1 this was a legitimate mail. Please visit
> 550-5.7.1 http://support.google.com/mail/answer/2451690 to learn about
> DMARC 550 5.7.1 initiative. ro6si3093371igb.36 - gsmtp (in reply to
> end of DATA command)"

It is not your problem, its yahoo's.  If enough people yell at or about 
their broken DMARC, maybe they will fix it  Their attitude seems to be 
that the whole world should be running it. Few others of yahoo's size 
are running it, and certainly not the broken yahoo version. FWIW, it did 
not cut the spam from yahoo servers by a noticeable amount here.  They 
have about as many compromised machines as ever.  Most of which I send 
to /dev/null with mailfilter before fetchmail even sees it. I suspect 
they may have in their IT staff, one or more admins that are making side 
money by posting spam, and sanitizing the logs immediately.

Thats pretty hard to detect unless you walkin on them in the act.

Cheers, Gene Heskett
-- 
"There are four boxes to be used in defense of liberty:
 soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)
Genes Web page <http://geneslinuxbox.net:6309/gene>