[Mailman-Users] Emails from yahoo members, are getting rejected by yahoo, "Service Unavailable".

[Joseph Brennan]

Jim Popovitch <jimpop at gmail.com> wrote:

> DMARC works off of SPF as well.

Not really. SPF does not check the "From:" header line, and that's where 
the troubles begin with DMARC.

Joseph Brennan
Columbia University IT