I'm seeing a disturbing (but minority) number of hosts that class our mail is spam. After some digging, I've found an interesting test case. What I'm uncertain of is if this represents a config error on our side or a (grossly) misbehaving mail host elsewhere.
The interesting test case is a correspondent with a private domain ([email protected]) and a gmail address ([email protected]), both of which deliver to his gmail address. That is, MX for example.com points to mx01.1and1.fr but the mail is still delivered to [email protected]. When I mail to [email protected], he receives the mail fine, and gmail reports that SPF, DKIM, and DMARC all pass. When I mail to [email protected], he receives the mail classed as spam, gmail reports that SPF is neutral, DMARC fails (and DKIM passes). Now what's odd is that gmail reports that SPF passes with the IP of my MX, but in the other case that it fails with the address of mout.kundenserver.de. We've confirmed that mout.kundernserver.de handles mail to him via 1and1.fr, but not what could be causing an issue. Mangling headers so badly to cause SPF/DMARC failures seems so egregious that I'm inclined to think it's somehow our fault. (Note: this is about mail for mobilitains.fr and not p27.eu.) -- Jeff Abrahamson +33 6 24 40 01 57 +44 7920 594 255 http://p27.eu/jeff/ http://mobilitains.fr/
