Title: Users may experience various issues when using the Microsoft Defender and Exchange Online Protection services
User impact: Users may have experienced various issues when using the Defender and Exchange Online Protection services.
More info: Impact included, but was not limited to:
– Delayed quarantined email notifications
– Delayed or erroring policy change propagation
– Delayed detection, message tracing, and reporting
– Delayed Advanced hunting reports
Final status: We’ve confirmed that the change reversion has completed successfully, and our telemetry shows that impact has been remediated.
Scope of impact: Any user hosted out of the affected infrastructure may have experienced impact when attempting to perform any of the functionalities outlined in the More info section of this communication.
Start time: Friday, October 20, 2023, at 6:00 AM UTC
End time: Friday, October 20, 2023, at 11:57 PM UTC
Root cause: A recent update led to a code regression within a portion of infrastructure responsible for facilitating some Defender and Exchange Online protection functionalities.
Next steps:
– We’re investigating how the recent update led to a code regression within a portion of infrastructure responsible for facilitating some Defender and Exchange Online protection functionalities to prevent this problem from happening again.
This is the final update for the event.
