Hello there,
This bug is in Windows Defender (KB5007651), a mandatory security update shipped alongside Windows 11's March 2023 Update. The issue seems widespread, and Microsoft is aware of the reports.
To fix “Local Security authority protection is off. Your device may be vulnerable”, follow these steps:
Open Windows Registry Editor.
Navigate to the following location: Computer\HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Lsa
Make sure you have RunAsPPL and RunAsPPLBoot. If you don’t have RunAsPPLBoot listed, create DWORD entries for RunAsPPL and RunAsPPLBoot.
The value for both entries should be 2.
Hope this resolves your Query !!
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