Postmastery supports SendGrid clients with multiple webhook endpoints

Postmastery provides delivery monitoring and optimisation services on top of various email delivery environments. Sometimes we offer this service on top of on-premises MTA (like PowerMTA or EmailSuccess) and sometimes on top of cloud-based ESP’s (like Mailchimp or Smartfocus). A prerequisite of delivery monitoring and optimization services, is to get the right data points like […]

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Categories: Authentication, General, Sendgrid, Solutions

New SMTP replies at Outlook: update your backoff patterns to avoid reputation damage

On April 5th, at 5AM CET, we were alerted by a huge spike in Outlook deferrals. The chart below (copied from Postmastery Delivery Analytics) reveals the deferrals over time: After investigating the issue, Postmastery delivery engineers discovered new SMTP replies at Microsoft domains. These errors are receiver’s side, not related to sender’s reputation. Organization queue quota […]

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Categories: Authentication, Deliverability, General, Providers

AOL and Yahoo merge could impact your email delivery and MTA

A few weeks ago, AOL reported that AOL and Yahoo will come together under the OATH umbrella and merge with the Yahoo email infrastructure to serve both brands. This happened on 20 February 2018, and now all the AOL recipient domains’ MX, including the following, will point to mx-aol.mail.gm0.yahoodns.net: – aol.com – verizon.net – aol.co.uk […]

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Categories: Authentication, Deliverability, General, PowerMTA, Providers

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