This one is stumping me. A client started to get their e-mail flagged as SPAM by some mail hosts, one being a major cable company in the area. Now we have the website/DNS holder, my client and the cable company going back and forth about why it is happening and who is responsible.
We have a 2003 exchange server behind a basic firewall. All incoming mail is filtered through Postini and all outbound goes through Postini. All inbound is fine, some outbound is not. They have had this setup for 2 years without issue, and then it suddenly started happening a couple months ago. The website/DNS folks say we need to program a PTR record in our firewall (huh?) How do you program that, isn't that a DNS thing? Then they were on to SPF records. So I had Postini give me their SPF record info. It was added to DNS but to no avail.
Is the cable company looking at Postini's info or are they looking back to the originating server. Do I need an SPF for our server as well as Postini's?
Does that make sense? We are not on any blacklists that I have tested (mxtoolbox among them) .