SparkPost outage, 12 November 2026
Microsoft outage: delays delivering to Outlook, Hotmail and Office 365
- Started
- Resolved
- 13 Nov 2026, 16:20 UTC (after 20 h 18 min)
- Impact
- Minor
- Affected
- Mailbox Provider Service Interruption
Is this still happening?
No. SparkPost marked this incident resolved on 13 Nov 2026, 16:20 UTC, 20 h 18 min after it began.
Right now: SparkPost reports all systems operational. (as of 13 Nov, 20:53 UTC) Live SparkPost status
At a glance
- SparkPost rated this a minor incident.
- It was resolved after 20 h 18 min. That is longer than a typical SparkPost incident: the median of the 26 other resolved ones we recorded is 2 h 15 min.
- SparkPost had 2 other incidents in the 30 days before it.
- 3 earlier incidents look like the same kind of problem (same affected part or wording); the most recent was on 27 Aug 2026.
Our summary from the SparkPost incidents we have recorded since 11 Dec 2025 - how we count.
Last update from SparkPost
This incident is resolved, and delivery to Microsoft mailboxes is back to normal. From about 17:30 UTC on 12 November, Microsoft's mail service returned temporary errors for most delivery attempts. The cause was an incident on Microsoft's side (Microsoft incident EX1550543), and delivery to other mailbox providers was not affected. Microsoft's errors dropped sharply from about 13:30 UTC on 13 November. Delivery was back to normal rates by 14:35 UTC, and Microsoft's error levels have been normal since about 15:10 UTC (09:10 CST). We queued all affected mail and retried it automatically. Most of it has now been delivered, and the rest of the retry queue will finish over the next few hours. Y...
Read the full incident on the official SparkPost status page
Similar SparkPost incidents
Earlier incidents with the same affected part or wording - useful to see how long this kind of problem usually takes.
-
, resolved after 23 h 42 min
-
, resolved after 4 h 53 min
Elevated hard bounces for Apple private relay recipients (privaterelay.appleid.com)
-
, resolved after 12 days
Other recent SparkPost incidents
-
Outbound message delivery is delayed/slow for some SparkPost customers (US hosted only)
-
Outbound message delivery is delayed/slow for some SparkPost customers (US hosted only)
-
Increased message delays in US and EU due to DNS resolution errors
-
Outbound message delivery is delayed/slow for some SparkPost customers (US hosted only)
-
Outbound message delivery is delayed/slow for some SparkPost customers (EU hosted only)
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