M365 Message Center

Geändert

28.04.2026

Services

Windows

IMPORTANT:This notice is only relevant for environments where:Visual Studio 2026 with .NET version 10.0.6 is used Scan Cab is used to check for update compliance The April 2026 Scan Cab was deployed before 10:30 AM PT on April 28, 2026 An updated version of the April 2026 Scan Cab was made available at 10:30 AM PT on April 28, 2026. This Scan Cab includes new metadata corresponding to updates for Visual Studio 2026. The Microsoft update for Visual Studio 2026 released on April 28, 2026, includes additional protections to address CVE-2026-40372: ASP.NET Core Elevation of Privilege Vulnerability. See the Additional information section of this message for details. How this affects your organization:IT administrators who downloaded the Scan Cab before 10:30 AM PT on April 28, 2026, should re-acquire and re-deploy it if the Scan Cab is used to assess updates for environments where Visual Stud

Geändert

27.04.2026

Services

Windows

Microsoft Defender now provides IT teams centralized visibility into Secure Boot 2023 certificate readiness across your device fleet. A new assessment categorizes your devices automatically as exposed, compliant, and not applicable. In the Defender portal, go to Exposure Management > Recommendations > Devices > Misconfigurations. For exposed devices, remediation guidance is directly available through the recommendation. When will this happen:The new Secure Boot 2023 certificate assessment is now available in Microsoft Defender. June 2026: Secure Boot 2011 certificates begin expiring and need to be replaced. How this will affect your organization:When certificates expire in June 2026, devices that haven't transitioned to the newer Windows UEFI CA 2023 certificates will no longer be able to receive new security protections for the early boot process. To help organizations prepare, Microsof

Geändert

23.04.2026

Services

Windows

Improve user experience with a single Microsoft Copilot app to use on any given device. The new RemoveMicrosoftCopilotApp policy setting allows you to uninstall Copilot from devices in your organization in a non-disruptive way. It only applies to devices and users that meet the following conditions: Microsoft 365 Copilot is also installed. Copilot wasn’t installed by the user. Copilot wasn’t launched in the last 28 days. It’s available as a Policy CSP and Group Policy. When will this happen:The policy is broadly available as of April 14, 2026. It’s part of the April 2026 Windows security update and later. How this will affect your organization:This policy simplifies the user experience by providing a single Copilot app to use on any given device. What you need to do to prepare:No action is needed if your organization prefers the default experience and allows users to use Copilot by choic

Geändert

22.04.2026

Services

Windows

Microsoft is hosting two upcoming Ask Microsoft Anything (AMA) events focused on updating Secure Boot certificate updates across your Windows estate before certificate expirations begin in June 2026. These AMAs are designed to help you get clarity on what’s changing and how to plan for deployment across your environment. Bring your questions and get practical guidance directly from Microsoft experts. When will this happen: Secure Boot certificates on Windows devices begin expiring in June 2026. The upcoming AMAs will take place on April 23, 2026 and May 18, 2026. What you need to do to prepare:Review the Secure Boot playbook to understand requirements, affected scenarios, and available tooling, then add one or both upcoming AMAs to your calendar:Secure Boot AMA – April 23, 2026, 8:00 AM PDT Secure Boot AMA – May 18, 2026, 8:00 AM PDT Post your questions in the comments section of each pa

Geändert

22.04.2026

Services

Windows

IMPORTANT: This notice is only relevant for environments where:ASP.NET Core is used Scan Cab is used to check for update compliance The April 2026 Scan Cab was deployed before 10:00 PM PT on April 21, 2026 An updated version of the April 2026 Scan Cab was made available at 10:00 PM PT on April 21, 2026. This Scan Cab includes new metadata corresponding to updates for ASP.NET Core. The Microsoft update for ASP.NET Core released on April 21, 2026, includes additional protections to address CVE-2026-40372: ASP.NET Core Elevation of Privilege Vulnerability. See the Additional information section of this message for details. How this affects your organization:IT administrators who downloaded the Scan Cab before 10:00 PM PT on April 21, 2026, should re-acquire and re-deploy it if the Scan Cab is used to assess updates for environments where ASP.NET Core is used. No action is required for envir

Geändert

19.04.2026

Services

Windows

Microsoft has released out-of-band (OOB) updates today, April 19, 2026, to address issues introduced by the April 2026 Windows security update. A limited number of Windows Server 2025 devices might experience failures installing the April 2026 security update (KB5082063). In addition, some versions of Windows Server may experience domain controllers restarting repeatedly after installing the April 2026 security update. To address these issues, Microsoft has released OOB updates for the Windows Server versions listed below. Note: The Windows Server 2025 OOB update (KB5091157) addresses both the installation failure issue and the domain controller restart issue. OOB updates released for other supported Windows Server versions address only the domain controller restart issue. For complete guidance and installation instructions, see the relevant KB articles: Standard Windows updatesWindows S