(Oops, forgot to include the list first time. Need more caffeine....) >An organization I know of is moving to o365 from their own mail system. >For a variety of reasons, the migration cannot be completely resolved >"day one". Thus, we concocted a scheme of keeping MX as is, and having >the current system simply relay messages to o365 and have users start >using o365 right away. > >Everyone thought this a great idea, solving several issues, until, >suddenly, last evening, I realized that we would be sending email that >might appear "spoofed". That is, from IP's that are not published as >"ours".
This is why SPF has "include" syntax. Check with the Microsoft rep for the exact details, but it will probably mean something like adding "include:spf.messaging.microsoft.com include:spf.protection.outlook.com" to your current SPF record. -- Dave Pooser Cat-Herder-in-Chief, Pooserville.com
