Microsoft 365 Service Updates for December 8 - 14, 2025

Microsoft 365 service updates scheduled primarily between December 2025 and early 2026, focusing heavily on security, feature retirements, and enhanced Copilot functionality. Key administrative actions include the urgent need to trust the DigiCert Global Root G2 CA for Entra services and update Office applications to maintain transcription features, while SharePoint is retiring the IDCRL protocol and enforcing modern authentication. Microsoft Teams is seeing several improvements, such as increased private channel limits and the ability to chat with users via email, while several legacy Planner features are being retired as part of a major update. A consistent theme across the updates is the introduction of new Copilot features in applications like Teams, Excel, and Outlook, alongside new admin dashboards for security posture and usage monitoring.