diecknet If you are still running Engine: 1.1.24020.9 /Platform: 4.18.24020.7 from the February release, then yes it's broken. Earlier, but also new versions work.
They should actually change that banner from "rolling back to the previous version is recommended." to "update to later release is recommended"...
Check this here: https://learn.microsoft.com/en-us/defender-endpoint/microsoft-defender-antivirus-updates#february-2024-engine-11240209--platform-418240207
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- The known issue in https://learn.microsoft.com/en-us/defender-endpoint/microsoft-defender-antivirus-updates#february-2024-engine-11240209--platform-418240207 where enforcement of device level access policies wasn't working as expected no longer occurs.
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I tested the latest version, all back to normal blocking behavior over here.