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Example bounces due to Yahoo p=reject

There are a number of different bounces that people are reporting due to Yahoo publishing a DMARC record of p=reject. I decided to put some of those bounces here so confused users could find out what they needed to do.
Comcast

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A brief DMARC primer

DMARC stands for Domain-based Message Authentication, Reporting and Conformance. What DMARC does is allow domain owners to publish policy statements in DNS telling receiver domains what to do with messages that do not authenticate. In addition, DMARC introduces the concept of “domain alignment.” What this means is that the authentication has to be from the same domain (or a sub-domain) as the address in the header-from: line. The idea behind DMARC is that organizational owners can use SPF and DKIM authentication to authenticate their actual domain in the header-from line. This moves authentication from a important but behind the scenes technology out to an end user visible technology.

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Dealing with DMARC for Mail intermediaries

I’ve been getting some mail and calls from folks looking for help on resolving the issue of DMARC bouncing. Some of these calls are from ESPs, but others are from SAAS providers who have users that have signed up with yahoo.com addresses and are now dealing with mail from those users bouncing, even when mail is going back too those users.
None of the solutions are really great, but here are a couple options.
1) Prohibit users users from sending with @yahoo.com header-from addresses. This will be challenging for some companies for all sorts of reasons. I have seen a number of people suggest switching to @hotmail.com or @gmail.com addresses. This only works as long as Gmail and Hotmail/Outlook don’t start publishing p=reject policies. It’s unclear if they’re even considering this at all, but it may happen.
2) Rewrite the header-from address from @yahoo.com to something you control. One thing I’ve been suggesting to customers is set up a specific domain for rewriting, like @yahoo.ESP.com. This domain would need to forward mail back to the @yahoo.com users, which does add another layer of complexity as these addresses will become spam magnets. Thus the forwarding IP should be on a distinct and separate IP, to prevent interference with other systems. Note, too, that any users sending to these reply addresses from a domain protected by DMARC p=reject will bounce.
If you have questions or want to ask specifically about what to do in your setup, I’ve blocked out some time in my schedule next week for companies. If you want more information about this please contact me to for available times, information requirements and pricing.

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