List-Unsubscribe header critical for sustained email delivery

In our daily work, we still encounter missing List-Unsubscribe headers in emails. Reason enough to publish another BLOG post on this important topic. Specially for PowerMTA users, we released an interesting add-on to streamline MAILTO unsubscribe requests. What is a List-Unsubscribe header? When subscribers want to unsubscribe from a mailing list and the unsubscribe process […]

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Categories: Case Studies, General, PowerMTA

Proper MIME prevents DKIM failures in Outlook

At Postmastery, we work for various ESPs and brands to optimise email delivery. Recently, one of our clients faced a mysterious DKIM failure when sending mail to Outlook.com domains. (A generic explanation of what DKIM is and how it works is available on dkim.org.) Analysing SMTP headers The first thing we did was to analyse the […]

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Categories: Authentication, General

Webinar PMTA insights

The Future of PowerMTA with Postmastery & Port25 On Tuesday 6 November, Postmastery and Port25 held a joint webinar. The webinar was a great success. Three panellists took part in an open conversation about the future of PowerMTA and the next steps. They answered questions from the PowerMTA community on topics that included: new developments […]

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Categories: General, PowerMTA