Microsoft's Secure Boot certificates, including the Microsoft Corporation KEK CA 2011, will expire on June 24, 2026, followed by the Microsoft UEFI CA 2011 on June 27 and the Microsoft Windows Production PCA 2011 on October 19. New certificates issued in 2023 will replace these older ones. While devices will continue to operate and receive standard Windows updates, they will gradually lose access to critical security updates that protect against boot-level threats. After June 24, the ability to sign new disallowed signature database payloads with the old KEK will be lost, reducing the capacity to revoke compromised bootloaders. Users are advised to keep Windows and firmware updates current, while enterprises may face challenges managing diverse machine inventories for updates.