Hello,
Thank you for posting in Q&A forum.
According to my investigation and research, I found that "Kernel-Mode Hardware-enforced Stack Protection" did disappear. Then I found in the Windows 11 update log that the May 9, 2023, update was related to it (as shown in the figure below), and it may be that the update caused this problem. Please refer to the link for more information: https://support.microsoft.com/en-us/topic/may-9-2023-kb5026372-os-build-22621-1702-ce93c18e-e819-458f-abcf-dc7154ce7e40
When you can't find this option in Windows Security Center, don't worry. This change is part of Windows Update to provide a better user experience and stronger security. This means your system is still protected and already benefits from this feature.
To ensure your system remains secure and up to date, I recommend that you keep your operating system and security patches up to date. This way you can ensure that your system has the latest security features, fixes, and other new features and performance improvements.
I hope the information above is helpful.
Best Regards,
Yanhong Liu
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