Extended Security Archives

Winsage

October 20, 2026

Microsoft Confirms October Windows Updates Can Break Exchange Server Email Services

Microsoft has acknowledged that the Windows Server security updates released on October 13, 2026, may disrupt Exchange Server email services, affecting on-premises systems running Exchange Server 2016, 2019, and the Subscription Edition. The disruptions can include blocked webmail access and undelivered messages. Microsoft has identified four specific Windows updates linked to these issues: KB5126646 for Windows Server 2025, KB5126655 for Windows Server 2022, KB5126651 for Windows Server 2019, and KB5126868 for Windows Server 2016. Symptoms may include inability to log into Outlook on the web, messages stuck in the Outbox, increased mail queues, and failed mailbox access. A critical error to monitor is MapiExceptionMdbOffline, and affected systems may log Event ID 1006. The October updates introduced a default limit of 512 simultaneous Endpoint Lookup calls, which can be exceeded under heavy Exchange workloads. Microsoft has provided a registry workaround to increase this limit and suggests monitoring for recurring failures. The disruption coincides with the end of the final paid update period for Exchange 2016 and 2019, with future updates limited to the Subscription Edition.

Winsage

October 20, 2026

Microsoft: October Windows Server updates break Exchange sign-in, mail flow

Microsoft has acknowledged that the latest Windows Server security updates are causing sign-in and mail delivery issues for certain Exchange Server systems, particularly affecting users of Windows Server 2019 and beyond. Affected customers report encountering a "MapiExceptionMdbOffline" error and Event ID 1006 in application logs. The October 2026 Windows security update has introduced a default limit on memory allocated to Endpoint Mapper, which may be insufficient under heavy load for Exchange Server workloads. Microsoft clarified that the reported issues are not related to the October 2026 Exchange server security updates and advised against uninstalling them. A temporary workaround involves modifying a registry key to increase the Endpoint Mapper memory limit. Additionally, Microsoft announced it would cease shipping extended security updates for Exchange 2016 and 2019 this month.

Winsage

October 18, 2026

Windows 11’s last Secure Boot deadline hits Monday, Microsoft reveals what happens to your PC

Microsoft Windows Production PCA 2011, the certificate for signing the Windows boot loader, will expire on October 19, 2026. This follows the earlier expiration of two other 2011 certificates in June 2026. PCs without the new certificates will still boot and receive standard updates but will miss out on new security enhancements for the early boot process. The new certificates from 2023 are replacing the 2011 certificates. The KEK certificate, essential for authorizing updates to signature databases, and the Microsoft UEFI CA 2011, which signs third-party boot loaders, will also be replaced by new certificates. Users can check their Secure Boot status through the System Information tool or Windows Security. Microsoft is gradually rolling out the new Secure Boot certificates through Windows Update, and users are advised not to disable Secure Boot to avoid complications. Dell will not issue BIOS updates for platforms that reached their end of service life before January 1, 2026. The transition to Secure Boot has faced challenges for older PCs, and developers are advised against pinning Secure Boot certificates in their applications. Multiple restarts may be required for full integration of the new certificates.

Winsage

October 15, 2026

NVIDIA Freezes Windows 10 GeForce Drivers in October: RTX 40-Series Misses DLSS 5 Support

On October 14, 2026, NVIDIA will release the final GeForce Game Ready Driver for Windows 10, coinciding with the operating system's mainstream end of support. Starting in November 2026, all new Game Ready and Studio Driver releases will only support Windows 11. Approximately 23.56% of Steam gamers were still using Windows 10 as of June 2026. The last Game Ready driver for Windows 10 is version 617.42, released on October 6, 2026. NVIDIA will provide quarterly security updates for Windows 10 GeForce drivers until October 2029, but no new game support or enhancements will be available. Users with RTX 20, 30, 40, and 50 series cards will be affected by this transition, while older models like the GTX 900 and GTX 10 series have already reached their support limits. Windows 10 users will miss out on DLSS 5, which is exclusive to RTX 50-series hardware. Microsoft has extended the free consumer Extended Security Update (ESU) program for Windows 10 to October 12, 2027.

Winsage

October 14, 2026

Microsoft: Windows 11 24H2 Home and Pro reached end of support

Devices operating on the Windows 11 24H2 Home and Pro editions have reached their end of support as of October 13, 2026, meaning they will no longer receive monthly security updates or non-security preview updates. In contrast, the Windows 11 24H2 Enterprise and Education editions will continue to receive mainstream support until October 12, 2027. Microsoft encourages users to transition to Windows 11 26H2, which will be supported until October 2029. The rollout of Windows 11 26H2 is phased and will expand over the next few months. Additionally, systems running Windows 11 23H2 Enterprise, Education, and IoT Enterprise editions will cease to receive security updates in 30 days after the end of support for Windows 11 23H2 Home and Pro editions in November 2025. Windows Server 2022 has also reached the end of its mainstream support but will remain under extended support until October 2031. Users are advised to upgrade unsupported versions of Windows to continue receiving security updates.

Winsage

October 14, 2026

Microsoft’s Record October Patch Tuesday Fixes 1,400+ Flaws As Windows Zero-Day Comes Under Attack

Microsoft's October 2026 security updates address 1,411 vulnerabilities, marking the largest Patch Tuesday release to date. The update includes 70 vulnerabilities classified as Critical, with 57 related to remote code execution, 11 to elevation of privilege, and two to spoofing. Key vulnerabilities include CVE-2026-96951, a Windows Shell security bypass being actively exploited, CVE-2026-108398, which affects .NET Framework and allows bypassing Windows Defender Application Control, and CVE-2026-92707, a denial-of-service vulnerability in MessagePack-CSharp. The release coincides with critical Windows support deadlines, with the final regular update for Windows 11 24H2 Home and Pro and Windows 10 Enterprise LTSB 2016 occurring on October 13. Organizations are advised to prioritize the exploited vulnerabilities, ensure relevant updates are applied, and validate application-control behavior.

Winsage

October 12, 2026

Microsoft Warns Windows Update Will Stop Working on Unpatched PCs Next Year

Microsoft is updating the certificates that authenticate communication between Windows PCs and Windows Update servers, with the current certificates expiring on May 17 and June 19, 2027. Users will generally not need to take action as the new certificates will be included in regular monthly security updates. Specific requirements for different Windows versions include: - Windows 11 25H2 and later: No action required. - Windows 11 24H2: Must install the September 2025 security update or newer. - Other supported Windows 11 and Windows 10 versions: Need the July 2026 update or later before June 19, 2027. - Windows 10 Enterprise 2019 LTSC, Windows Server 2019, and Windows Server 2016: Deadline of May 17, 2027. Devices running unsupported versions will lose access to Windows Update services. Home users with Windows 10 PCs not enrolled in Extended Security Updates (ESU) after October 2025 may miss the critical July 2026 patch. Microsoft has extended ESU coverage until October 12, 2027. Users should check their update history to ensure they have received a cumulative update from July 2026 or later.

Winsage

October 7, 2026

Users are finally switching over to Windows 11 — mainly because the cost of staying on Windows 10 is set to soar

Windows 10 is expected to see a decline in its user base due to rising costs of Extended Security Updates (ESUs), which total approximately per device for three years. Historically, user loss accelerates after the third year of support ends, as seen with Windows 7. In contrast, Windows 11 is experiencing significant growth, commanding 71.5% of all Windows installations as of September 2026, following a stagnant year. This increase is linked to the end of support for Windows 10 in October 2025, prompting migrations to Windows 11.

Winsage

October 7, 2026

Windows 11 gains ground as price hike looms for Windows 10 security updates

Microsoft has extended its Windows 10 Extended Security Updates (ESU) program, allowing consumers to receive security updates at no cost until October 12, 2027. Businesses must pay to enroll, with a tiered pricing structure: the first year costs per device, the second year costs 2 per device, and the third year costs 4 per device. This price increase may encourage organizations to transition to Windows 11.

Winsage

October 1, 2026

Windows 10 Users Face a $30 Choice as Microsoft Quietly Extends Security Support to 2027

Microsoft has extended the support cutoff for Windows 10 from October 13, 2026, to October 12, 2027, due to a one-year extension of the consumer security program. Devices enrolled in the Extended Security Updates (ESU) program will continue to receive updates automatically. Unenrolled devices can still enroll until October 12, 2027, to receive critical updates released since their support ended on October 14, 2025. Users in the European Economic Area can access ESU at no extra cost but must maintain a Microsoft account to avoid losing access to updates after 60 days. To qualify for ESU, devices must run Windows 10 version 22H2 in supported editions, have the latest updates, and meet specific criteria. Microsoft 365 Apps and OneDrive on Windows 10 will receive updates beyond ESU, but the operating system itself remains unprotected without ESU. As of August 2026, 25.15 percent of Windows desktops in Germany were still using Windows 10. Users can check their ESU status under Settings, Update & Security, Windows Update.