Microsoft 365 Alert – Service Degradation – Planner – Users see a blank page when opening Planner – RESOLVED

Announcements Sharmista Mohanta

27/08/2026 11:19:00 AM

NHSmail Reference: INC46920476

Microsoft Reference: PL1462280

Issue Status: RESOLVED

Issue Description: Users saw a blank page when opening Planner.

More Info: Impact was specific to non-English users.

Final Update: 27/08/2026 11:20:00 AM – Microsoft has identified that a recent build release introduced a configuration issue where code wasn’t localized for non-English locales, resulting in an “undefined” handle and impact. They have completed their process to revert this build and confirmed with a subset of affected users that impact was successfully remediated.

Scope of impact: Your organisation was affected by this event, and non-English users were impacted.

Root cause: A recent build release introduced a configuration issue where code wasn’t localised for non-English locales, resulting in an “undefined” handle and impact.

Next steps: Microsoft is reviewing their build testing and validation procedures to identify opportunities to improve impact detection and better prevent similar future occurrences.