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ChangesSparkPostMicrosoft outage: delays delivering to Outlook, Hotmail and Office 365

SparkPost: Incident updated: Microsoft outage: delays delivering to Outlook, Hotmail and Office 365

Incident updateNot classified yetChanged status.sparkpost.com (opens in new tab)
Summary

Summary pending. The diff below shows exactly what changed.

Incident page: the full timeline of updates

What changed

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AddedUpdateidentified#1
Before: not present
After: We're still monitoring Microsoft incident EX1550543. Delivery to Outlook.com, Hotmail, Live, MSN and Office 365 recipients is still heavily delayed, and we haven't seen a meaningful improvement. In its latest update, Microsoft said its earlier recovery steps did not bring the expected relief. It has traced the problem to a core process on its servers that is becoming overwhelmed. Microsoft is now isolating part of its infrastructure, restarting it and slowly bringing traffic back to test a recovery approach before applying it more widely. It has not given a time for recovery, and its next update is expected by 23:30 UTC. You can follow it at https://status.cloud.microsoft/m365/referrer=serviceStatusRedirect. SparkPost's systems are working normally. We're still queuing messages to Microsoft and retrying them automatically, and some continue to get through on a retry. Please don't resend affected messages, because that will create duplicates once the queued mail is delivered. Because this has now lasted several hours, messages with an expiration time of up to a few hours may also expire before Microsoft accepts them, not only very short ones. You'll get a bounce event for each expired message.

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History of this incident

TodayFriday, November 13Fri, Nov 13

3 incident changes

YesterdayThursday, November 12Thu, Nov 12

2 incident changes

Cite this

Incident updated: Microsoft outage: delays delivering to Outlook, Hotmail and Office 365 on SparkPost’s status page, changed 2026-11-12 22:33 UTC (change 2 of 5).

Title
Incident updated: Microsoft outage: delays delivering to Outlook, Hotmail and Office 365
Vendor
SparkPost
Date
URL
https://rewindex.com/change/r403c7e39cf13b3

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