Earlier this month, I published a post about some changes with how Google is displaying information related to authentication in their “View Original” page. There’s one condition I apparently didn’t report and it brought up a question earlier today. If a message has alignment between DKIM and the 5322.from address but there is no DMARC record for that domain published in...
Google, Alignment and DMARC
Google has been making a number of changes to their systems over the last few weeks. Folks are seeing a lot of changes in Google postmaster tools and they’re seeing changes in how Google is displaying headers in the “show original” tab. One thing that some folks were seeing is a message that says: This “Alignment” description replaced the DMARC verdict in the header...
Don’t add your domain to the Public Suffix List
Adding your domain to the public suffix list might break all your email.
Do we care about SPF alignment?
Do we really care whether our SPF email authentication is aligned?
Sending domains and hostnames
Lots of times I see someone asking a question and they talk about their sending domain. And it’s sometimes not 100% clear which domain they mean by that – and when we’re talking about alignment and reputation it can make a difference. So here’s a list of (some of?) the different places a mailserver uses a domain. Hostnames Machine Hostname: What the operating system...
DMARC: The good, the bad and the ugly
DMARC is the newest of the authentication protocols. It compares the domain in the From: address to the domains authenticated by SPF and DKIM. If either SPF or DKIM pass and they are in the same organizational domain as the domain in the From: address then the email is authenticated with DMARC. I wrote A Brief DMARC primer back in 2014 – when Yahoo deployed p=reject late on a Friday and...
Wildcards and DKIM and DMARC, oh my!
If you’re an ESP with small customers you may have looked at the recent Google / Yahoo requirements around DMARC-style alignment for authentication and panicked a bit. Don’t impersonate Gmail From: headers. Gmail will begin using a DMARC quarantine enforcement policy, and impersonating Gmail From: headers might impact your email delivery.…For direct mail, the domain in the...
Don’t break the (RFC) rules
It looks like Microsoft are getting pickier about email address syntax, rejecting mail that uses illegal address formats. That might be what’s causing that “550 5.6.0 CAT.InvalidContent.Exception: DataSourceOperationException, proxyAddress: prefix not supported – ; cannot handle content of message” rejection. Why do we care? It’s good to send syntactically valid...
Gmail Program for Election Mail
A few months ago, Google made a splash in the political press and the email marketing space when they asked the FEC the following question: May Google launch a free and non-partisan pilot program to test Gmail design features, which will be open to authorized candidate committees, political party committees, and leadership political action committees, where spam detection as applied to messages...
Authentication at Office365
This is a followup from a post a few weeks ago about authentication changes at Office365. We have some more clarity on what is going on there. This is all best information we have right now. Microsoft is now requiring authentication to match the visible from address in order to reach the inbox at Office365. That means, either the SPF domain or the DKIM domain must align (in the DMARC sense) to...