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Microsoft Rolls Out Automatic Secure Boot Certificate Replacement in Windows 11

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Updated March 21, 2026 at 02:52 PM3 sources
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Microsoft Rolls Out Automatic Secure Boot Certificate Replacement in Windows 11

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Microsoft began automatically replacing expiring Secure Boot certificates on eligible Windows 11 24H2 and 25H2 devices via Windows quality updates, using a phased rollout that targets “high-confidence” devices based on successful update signals. The change follows earlier warnings that commonly used Secure Boot trust anchors will start expiring in June 2026, which could disrupt secure boot validation on UEFI systems if not remediated. Secure Boot relies on firmware-stored certificates to verify bootloader signatures and prevent pre-boot malware (e.g., rootkits) from loading.

Microsoft warned that failing to update these certificates can lead to loss of Windows Boot Manager trust and Secure Boot protections, and may prevent devices from receiving future security updates for pre-boot components—creating both availability and security risk. For organizations that need tighter control, Microsoft also provides manual deployment options (e.g., via registry-based methods and enterprise management tooling such as policy/configuration controls) to ensure certificate updates are applied ahead of expiration and to validate Secure Boot status across fleets.

Timeline

  1. Jan 13, 2026

    Microsoft warns June 2026 certificate expirations could weaken boot security

    Microsoft said commonly used Secure Boot trust anchors are expected to begin expiring in June 2026, which could disrupt secure booting, reduce Windows Boot Manager and Secure Boot protections, and block future pre-boot security updates if devices are not updated. The company also advised organizations to inventory devices, verify Secure Boot status, apply OEM firmware updates, and use manual deployment options such as registry keys, WinCS, or Group Policy where needed.

  2. Jan 13, 2026

    Microsoft begins phased Secure Boot certificate updates for Windows 11

    Microsoft started automatically rolling out refreshed UEFI Secure Boot certificates to eligible Windows 11 24H2 and 25H2 devices through monthly quality updates. The phased deployment uses targeting and update-success signals to identify systems ready for the certificate replacement.

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