----- Original Message ----- From: "Erik (Caneris)" <erik_list@caneris.com> To: "Joe Abley" <jabley@hopcount.ca>; "Micheal Patterson" <micheal@spmedicalgroup.com> Cc: <nanog@nanog.org> Sent: Tuesday, February 24, 2009 9:11 PM Subject: RE: Yahoo and their mail filters.. Ditto. They appear to use some strange form of greylisting combined with blocking. What seems to help is SPF and PTRs that match the EHLO your MTAs will send. We didn't implement Domain Keys / DKIM. On a related note, don't get me started on Hotmail. They used to (still do?) silently swallow mail into a black hole after accepting it. No NDR, no spam folder, just good ol' mail shredding without anyone knowing. Again, SPF and PTRs seem to help. Oh yeah, make sure you're not sending spam to them. That might help too. ;) Erik SPF records aren't being recognized, I've been running them for some time now so it would seem that they're not honoring them. -- Micheal Patterson