Microsoft 365 Alert – Service Degradation – Microsoft Teams – Some users” apps, such as the Calendar and OneDrive, aren”t appearing in the Microsoft Teams sidebar – RESOLVED

21/03/2025 08:26:00 AM

NHSmail Reference: INC46482661

Microsoft Reference: TM1037342

Issue Status: RESOLVED

Issue Description: Users” apps, such as the Calendar and OneDrive, weren”t appearing in the Microsoft Teams sidebar.

Current Update: 21/03/2025 08:26:00 AM – Microsoft’s have completed restarting the cache of users on affected portions of Microsoft Teams service infrastructure and received confirmation from some users who initially reported the issue that the impact is remediated.

Scope of impact: Users whose requests were processed through the affected portion of infrastructure may not have been presented with some side bar apps, such as Calendar and OneDrive, in the Microsoft Teams sidebar of the

Root cause: A portion of Microsoft Teams service infrastructure, which facilitates populating the app sidebar, had a misconfiguration that resulted in users whose requests were processed through the affected infrastructure to not be populated or supported.

Next update by: Microsoft are further reviewing the portion of Microsoft Teams service infrastructure to identify what caused the misconfiguration, and to prevent similar impact scenarios from reoccurring.