It is somewhat common for the Patch Tuesday OS security updates to break something, and the ones for March were no different. The updates introduced an issue with the Windows Security app wherein Microsoft Defender would wrongly report that the Local Security Authority (LSA) protection was off. It affected both Windows 11 22H2 as well as 21H2.
The company stated:
After installing "Update for Microsoft Defender Antivirus antimalware platform - KB5007651 (Version 1.0.2302.21002)", you might receive a security notification or warning stating that "Local Security protection is off. Your device may be vulnerable." and once protections are enabled, your Windows device might persistently prompt that a restart is required. Important: This issue affects only "Update for Microsoft Defender Antivirus antimalware platform - KB5007651 (Version 1.0.2302.21002)". All other Windows updates released on March 14, 2023 for affected platforms (KB5023706 and KB5023698), do not cause this issue.
Microsoft provided a workaround for the issue at that time as it was still investigating the bug. After a month passed since then, the company announced that it was able to resolve the issue and the solution was to update to Defender version 1.0.2303.27001.
However, this victory of Microsoft was short-lived as the issue returned, as it never left for some, including one of Neowin forum members kiddingguy. Today, the Windows health dashboard issues section was updated by the tech giant as it claims that the LSA off issue has been finally resolved.
Microsoft says that the Defender version 1.0.2306.10002. Essentially, all you need to do is update to the latest version of Windows Security app via the Windows Update, and the issue should go away. Microsoft writes:
Resolution: This issue was resolved in an update for Windows Security platform antimalware platform KB5007651 (Version 1.0.2306.10002). If you would like to install the update before it is installed automatically, you will need to check for updates.
You can discuss the issue on this thread on our forum. Also, let us know in the comments below if you are still affected by the LSA bug even after applying the update.