
Countdown to Secure Boot: What If You Miss the June 2026 Certificate Update on Windows 11
Microsoft explains that the original Secure Boot certificates (2011) expire in June 2026 and will be replaced by 2023 certificates through a phased CFR/LCU rollout. Legacy BIOS devices won’t be updated, and Secure Boot must be enabled; the process may involve several reboots and resealing BitLocker keys. If you ignore the deadline, Windows will boot but security will be degraded because boot-critical updates and DBX revocation lists won’t be applied, potentially blocking future OS upgrades that rely on the 2023 chain. Enterprises should test deployments, monitor Secure Boot status in Windows Security, and plan PXE/boot-manager changes accordingly. Servers require manual intervention, and the 2023 certs are projected to last until 2038 with further shifts toward post-quantum certificates later on.









