SEDNA incident
Microsoft Incident - Users may experience delays sending and receiving email messages
SEDNA experienced a minor incident on August 29, 2025, lasting 2h 36m. The incident has been resolved; the full update timeline is below.
Update timeline
- investigating Aug 29, 2025, 01:36 PM UTC
As per Microsoft: ID: EX1144276 Issue type: Incident Status: Service Degradation Impacted services: Exchange Online Details: Title: Users may experience delays sending and receiving email messages User impact: Users may experience delays sending and receiving email messages. Current status: We're reviewing service monitoring telemetry to isolate the source of the issue and establish a fix. Scope of impact: Some users who are located in Europe attempting to send or receive Exchange Online email messages may be impacted. Next update by: Friday, August 29, 2025, at 2:30 PM UTC
- investigating Aug 29, 2025, 01:38 PM UTC
Aug 29, 2025, 4:38 PM GMT+2 The new throttling rule has successfully been deployed. We’ve received confirmation from some of the previously affected users that they can now send and receive email. Additionally, our telemetry shows that the new throttling rule is having the desired effect and providing relief. Next update by: Friday, August 29, 2025 at 6:00 PM GMT+2
- investigating Aug 29, 2025, 04:12 PM UTC
Aug 29, 2025, 5:38 PM GMT+2 After monitoring the service and receiving confirmation from previously affected users, we’ve confirmed that impact has been remediated. The service will now resume periodic attempts to deliver emails that were sent during the impacted period. Issue details Issue ID: EX1144276 Affected services: Exchange Online Status: Service restored Start time: Aug 29, 2025, 12:36 PM GMT+2 End time: Aug 29, 2025, 5:10 PM GMT+2 Issue type: Incident
- resolved Aug 29, 2025, 04:13 PM UTC
This incident has now been resolved