Hi @Tomasz W ,
If the update is superseded, it will show as Not required, but on the side of windows update, the update could be scanned and installed. So we should check if the update is superseded on the sccm console or update catelog.
For example:
This update is superseded and is not required on the console,
And on the update catelog:
As we said, there is no wrong with Microsoft Defender (those are working properly), so it maybe nothing wrong with WUAHandler, if monthly updates or products like Visual Studio are not superseded, we could run the Software Updates Scan Cycle and check UpdatesHandler.log, WUAHandler.log and ScanAgent.log.
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