Microsoft is retiring the Microsoft 365 companion apps—Calendar, People, and Files—on December 16, 2026. These apps were automatically installed on Windows 11 enterprise devices starting December 2025 to provide contextual AI assistance and quick access to organizational resources. Microsoft has stopped installing these apps and advises admins to remove them before the retirement date, after which the apps will cease functioning and support. This announcement is part of Microsoft's lifecycle management and does not indicate any security vulnerabilities or active exploits related to these apps. The company also advises migration to phishing-resistant authentication methods for Entra ID users ahead of SMS sign-in retirement in February 2027.

There is no direct security impact or vulnerability associated with the retirement of these apps. The main impact is operational: organizations must remove the apps from managed devices to avoid unsupported software presence. Users will lose the functionality provided by these companion apps after December 16, 2026. There are no reported exploits or security threats linked to this retirement.

Microsoft has officially ended support for the Microsoft 365 companion apps and stopped their installation. Administrators should proactively remove these apps from managed devices before December 16, 2026, to maintain a supported environment. Users of unmanaged devices should uninstall the apps themselves. No security vulnerabilities or exploits are reported, so no additional security mitigations are required related to these apps. Additionally, admins should migrate Entra ID users to phishing-resistant authentication methods to prevent sign-in disruptions starting February 2027.