Microsoft's original Secure Boot certificates — issued in 2011 — begin expiring in June 2026. Unlike Windows 11, Windows Server does not receive these updates automatically via Windows Update. Administrators must manually deploy the 2023 replacement certificates to all applicable servers and Generation 2 virtual machines before the deadline. Systems that remain on the 2011 certificates after expiration enter a degraded security posture and cannot receive future Secure Boot updates.
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