Outage in Postmark

Microsoft Deliverability Issues (Outlook, Hotmail)

Resolved Major
August 29, 2025 - Started about 2 months ago - Lasted 18 days
Official incident page

Incident Report

We are experiencing Broadcast email deliverability issues for Microsoft domains such as Outlook and Hotmail. Office 365 emails are delivering as expected. Engineering and Deliverability teams are actively investigating the situation.

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