by Francis Rozange | Sep 8, 2026 | Emailing
Google requires it of bulk senders. So does Yahoo. Everyone calls it “one-click unsubscribe”, and almost everyone believes it means a link to put in the message. It is a protocol. It fits in a nine-page specification, published in January 2017 as RFC 8058,...
by Francis Rozange | Sep 8, 2026 | Emailing
DKIM signs your messages. It is the only one of the three authentications that survives a forward, the only one Yahoo requires before telling you who complained, and the only one without which your one-click unsubscribe button does not appear. It is also the one you...
by Francis Rozange | Sep 8, 2026 | Emailing
Your SPF record fits on one line. It declares who is allowed to send mail in your name, and it looks like this: v=spf1 include:_spf.google.com include:sendgrid.net include:servers.mcsv.net include:_spf.salesforce.com ~all Four providers, four includes, one perfectly...
by Francis Rozange | Sep 8, 2026 | Emailing
For eleven years DMARC was an informational document. Published in March 2015 as RFC 7489, it had not even gone through the IETF’s standards process: it arrived through the independent submission stream, with Informational status. In other words, the mechanism...
by Francis Rozange | Sep 8, 2026 | Emailing
On 2 April 2025, Microsoft announced that domains sending more than five thousand messages a day to Outlook.com and Hotmail would have to authenticate their mail. SPF, DKIM, DMARC at p=none minimum, aligned on one of the two. Enforcement on 5 May. On 29 April, six...
by Francis Rozange | Sep 8, 2026 | Emailing
Google publishes a threshold: five thousand messages a day. Microsoft publishes the same. Yahoo, asked about its own, answers this: “A ‘bulk’ sender is classified as an email sender sending a significant volume of mail. We will not specify a volume...