Microsoft 365 Alert – Service Degradation – Exchange Online – Admins may be unable to update Dynamic Distribution Group (DDG) memberships – RESOLVED

Announcements Arpan Das

24/04/2025 08:57:00 AM

NHSmail Reference: INC46513453

Microsoft Reference: EX1061148

Issue Status: RESOLVED

Issue Description: Admins may be unable to update Dynamic Distribution Group (DDG) memberships

More info: Additionally, members of the DDG automatic updates are failing, even after forcing refresh with the ‘-ForceMembershipRefresh’ switch.

Final Update: 29/04/2025 09:11:00 AM – Microsoft’s have confirmed through monitoring service health telemetry that reverting the impacting service update successfully resulted in the exception counts returning to expected values, and the impact is remediated.

Scope of impact: Admins attempting to update DDG memberships and users attempting to receive DDG automatic updates may be impacted.

Root cause: The piece of infrastructure responsible for updating DDG memberships wasn’t included within a recent service update, resulting in impact.

Next Steps: Microsoft are further reviewing the recent service update testing and validation procedures to understand what prevented us from detecting that the piece of infrastructure responsible for updating DDG memberships wasn’t targeted and therefore could result in this impact, which will allow us to prevent similar issues in future updates.