Gmail / Apps authentication issues

I’ve seen several reports of unexpected rejections for unauthenticated email to Google over IPv6 today. Unauthenticated mail over IPv6 is a bad idea, but Google usually spam folders it rather than rejecting it.
The Gmail status dashboard is reporting an issue “Some messages sent to consumer Gmail accounts are being rejected due to authentication enforcement” so something isn’t working as intended.

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May 2016: The Month in Email

Summer, already? Happy June! Here’s a look at our busy month of May.
201605Wrapup
I had a wonderful time in Atlanta at the Salesforce Connections 2016 conference, where I spoke on a panel about deliverability. While in Atlanta, I also visited our friends at Mailchimp, and later spoke at the Email Innovations conference in Las Vegas, where I did my best to avoid “explaining all the things”. Since my speaking schedule for 2017 is filling up already, I’m sure I’ll have plenty of opportunity to explain many more of the things over the next year or so. Let me know if there’s an event that might be a good fit for me, either as a keynote speaker or on a panel.
Steve contributed a few technical posts on the blog this month. He mentioned that Google has stopped supporting the obsolete SSLv3 and RC4, and he explored the ARC protocol, which is in development and review, and which will be useful in extending authentication through the email forwarding process.
Meri contributed to the blog this month as well, with a post on the Sanders campaign mailing list signup process. We’ve written about best practices for political campaigns before, and it’s always interesting to see what candidates are doing correctly and incorrectly with gathering addresses and reaching out to supporters.
In other best practices coverage, I pointed to some advice for marketers about authentication that I’d written up for the Only Influencers list, a really valuable community for email marketers. I wrote about purchased lists again (here’s a handy collection of all of my posts on the topic, just in case you need to convince a colleague that this isn’t a great idea). I also wrote about how getting the technical bits right isn’t always sufficient, which is also something I’ve written about previously. I also discussed the myth of using the word “free” in the subject line. As I said in the post, “Single words in the subject line don’t hurt your delivery, despite many, many, many blog posts out there saying they do. Filters just don’t work that way. They maybe, sorta, kinda used to, but we’ve gotten way past that now.”
On a personal note, I reminisced about the early days of mailing list culture and remembered a dear online friend as I explained some of why I care so much about email.
In my Ask Laura column, I covered CAN SPAM and transactional opt-outs. As always, if you have a general question about deliverability that I can answer in the column, please let me know.

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A DKIM primer resurrected

I was looking for some references today back in old blog posts. This means I discover some old links are dead, blog posts are gone or moved, and information is lost.
In this case it’s a post by J.D. Falk on deliverability.com. The link is dead (it looks like the whole website is dead), but I found a copy of his post and am reproducing it here. I don’t have permission, because I can’t get permission from him, but the content is extremely useful and I don’t want it lost.

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Gmail shows authentication data to the recipient

Yesterday Gmail rolled out some changes to their interface. One of the changes is that they are now showing end users authentication results in the user screen.
It’s really the next step in email authentication, showing the results to the end user.
So how does Google do this? Google is checking both SPF and DKIM. If mail is authenticated and the authentication matches the from address then they display the email as:
mail from steve to me
If we click on “details” for that message, we find more specific information.
full details of message showing signing domain and spf domainIn this case the mail went through our outgoing mailserver to gmail.
Mailed-by indicates that the message passed SPF and that the IP address is a valid source of mail from wordtothewise.com.
Signed-by shows the domain in the DKIM d=. In this case, we signed with the subdomain dt.wordtothewise.com. That’s what happens when you sign using the domain in the From address (or a subdomain of it).
For a lot of bulk senders, though, their mail is signed using their ESP’s domain instead.  In that case Gmail shows who signed the mail as well as the from address.

And when we click on “details” for that message we see:
3rd party signature detailsThis is an email from a sender using Madmimi as an ESP. Madmimi is handling both the SPF authentication and the DKIM authentication.
As an aside, this particular  sender has a high enough reputation that Gmail is offering me an unsubscribe option in their interface.
Gmail is distinguishing between first party and third party signatures in authentication. If the mail is authenticated, but the authentication appears to be handled by a separate entity, then Gmail is alerting recipients to that fact.
What does this mean for bulk senders?
For senders that are signing with a domain that matches their From: domain, there is no change. Recipients will not see any mention of your ESP in the headers.
However, if you are using an ESP that is signing your mail with a domain they own, then your recipients will see that information displayed in the email interface. If you don’t want this to be displayed by Gmail, then you will need to move to first party signing. Talk to your ESP about this. If they’re unsure of how to manage it, you can point them to DKIM Core for an Email Service Provider.
Gmail blogpost about the changes
Gmail help page about authentication results

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