@z080236
Hi,
Did you mean you cannot apply the KB4052623? When did this appear and what's the detailed error message?
This update is available for Windows Server 2019 and Windows Server 2016.
Microsoft Defender Antivirus uses cloud-delivered protection. Cloud-delivered protection is always on and requires an active connection to the Internet to function.
I suggest you use Windows Defender when connect to the Internet.
Hope above information can help you.
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