Update - Office 365 is still normal; Hotmail is still slow, but mail is getting through. Microsoft's service health status is still shows a service degradation (https://status.cloud.microsoft/).
Nov 13, 2026 - 15:23 EST
Nov 13, 2026 - 15:23 EST
Update - Microsoft 365 business addresses are back to normal while Outlook and Hotmail personal addresses are still seeing some delays.
Nov 13, 2026 - 14:44 EST
Nov 13, 2026 - 14:44 EST
Update - Microsoft is still having a service disruption affecting Outlook, Hotmail, and Microsoft 365, and its status page continues to show degraded service. Since this morning, Microsoft has been accepting mail more slowly than usual, so newsletters sent to these addresses may arrive later than expected.
Delayed messages are queued and retried automatically. Most arrive within a few hours, and no action is needed on your part. A small number of messages sent during the disruption could not be delivered.
Delivery to Gmail, Yahoo, and other providers is not affected. We’re watching this closely and will post again when delivery to Microsoft returns to normal.
Nov 13, 2026 - 10:39 EST
Delayed messages are queued and retried automatically. Most arrive within a few hours, and no action is needed on your part. A small number of messages sent during the disruption could not be delivered.
Delivery to Gmail, Yahoo, and other providers is not affected. We’re watching this closely and will post again when delivery to Microsoft returns to normal.
Nov 13, 2026 - 10:39 EST
Update - We’re seeing renewed delivery delays to Outlook, Hotmail, and Microsoft 365 addresses as Microsoft’s service disruption continues. Messages are queued and being retried automatically, and most will arrive late rather than not at all. A small number may not be delivered. We’ll update this page as Microsoft’s service recovers.
Nov 13, 2026 - 07:49 EST
Nov 13, 2026 - 07:49 EST
Update - There isn't much to report (https://status.cloud.microsoft/m365/). Hotmail is easing, but Office 365 is still in bad shape, turning away hundreds of thousands of emails. We will continue monitoring and will update this status when there's news.
Nov 12, 2026 - 17:55 EST
Nov 12, 2026 - 17:55 EST
Update - A small update. New mail is mostly getting through, while messages already held earlier keep being retried and turned away. Hotmail messages are bouncing at a 5x rate than normal, but Letterhead won't treat those as cleaned, so you're not at risk of losing subscribers.
Nov 12, 2026 - 16:00 EST
Nov 12, 2026 - 16:00 EST
Monitoring - Microsoft is currently experiencing a service disruption affecting Outlook, Hotmail, and Microsoft 365. Since about 1:00 PM ET today, Microsoft’s mail servers have been temporarily declining new messages, so newsletters sent to those addresses may arrive later than usual.
Your sends are not lost. Messages to Microsoft addresses are queued and retried automatically, and they’ll be delivered as Microsoft’s service recovers. Delivery to Gmail, Yahoo, Apple, and other providers is not affected.
You don’t need to resend or reschedule anything. Open rates for Microsoft recipients on today’s sends may look low until the delayed messages arrive.
We’ll update this notice as Microsoft’s service recovers.
Nov 12, 2026 - 15:13 EST
Your sends are not lost. Messages to Microsoft addresses are queued and retried automatically, and they’ll be delivered as Microsoft’s service recovers. Delivery to Gmail, Yahoo, Apple, and other providers is not affected.
You don’t need to resend or reschedule anything. Open rates for Microsoft recipients on today’s sends may look low until the delayed messages arrive.
We’ll update this notice as Microsoft’s service recovers.
Nov 12, 2026 - 15:13 EST
API
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Applications
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Archives
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Polls
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Letterhead for Chrome
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Delivery
Degraded Performance
Outbound Email Deliverability (Shared Pools)
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Outbound Email Deliverability (Dedicated Pools)
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Degraded Performance
Partial Outage
Major Outage
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Major outage
Partial outage
No downtime recorded on this day.
No data exists for this day.
had a major outage.
had a partial outage.