jchance - 5:08 am on Apr 8, 2006 (gmt 0)

Having receintly gone through this pain of getting our company's mail past the yahoo, msn, gmail, aol, spam filters, I can provide some info.

SPF - This is critical, especially for gmail and yahoo. Microsoft has a "Sender ID" (of course, microsoft has to rename it right) creation tool that you can use to generate your spf record:
[microsoft.com...]

DomainKeys - I was never able to find any useful info on implementing it with exim. If someone has info, I would love to see it. I was able to get by the Yahoo spam filters without it, so I guess if they are using it, obviously its just a piece of their spam system.

However, in order to get past the yahoo spam filter I had to contact yahoo directly. Goto: [postmaster.yahoo.com...] where you can fill out a long form promising to be good.

RDNS - This is critical. Without it, you won't get past any spam filters. Your hosting company will have to set this up for you.