Thanks John. This was a common question that was asked off-list. That edge MTA is not used and has never been used by anything/anyone other than us. No customer mail flows or has flowed in or out via it ever.
As I mentioned in my follow-up post, the issue at this point is that the domain has been blacklisted. I can send an identical message from the same MTA, changing only the From header, and it will be delivered to Inbox. Only when the From header contains @caneris.com will the message be delivered to spam. Any changes to the MTA IP, content, headers, etc. don't have any effect. Erik ----- Original Message ----- From: "John Levine" <jo...@iecc.com> To: nanog@nanog.org Cc: "erik list" <erik_l...@caneris.com> Sent: Wednesday, September 29, 2010 1:58:28 PM Subject: Re: What must one do to avoid Gmail's retarded non-spam filtering? >We have proper A+PTR records on the edge MTAs, proper SPF records for >the originating domain, proper Return-Path and other headers, and so >on. There isn't anything that I can think of other than the content >itself which would be abnormal, and obviously the content is >repetitive and can't be changed much. Is there something obvious >which we've missed? What else goes out from that MTA? User forwarded mail? Mailing lists? random customer junk? It is a really good idea to separate your mail streams. These days it means separate IPs for users, transactions, forwards, and such, eventually different DKIM signatures will do the trick. R's, John
