The malicious software removal tool is updated monthly and is cumulative in
what it covers. It runs once as part of the security updates on second
Tuesdays--there's no user interface, but it leave a log file behind. If it
finds something, I believe there is some notice to the user--I've never seen
this so I don't know what it is like.
If you google malicious software removal tool home, the tool has a home page
where you can either run it from the web page, or download it to a location
of your choice.
Yes--you absolutely need the Malicious Software removal tool--it is very
minimal in system impact--runs for seconds once a month--and it targets
rootkit families--really nasty stuff.
I believe that the update in place in your Windows Defender install is not
fully installed--thus the repeated-offer from the update site. Windows
Defender is designed to automatically get its updates via Autoupdate, which
may go directly to Microsoft for a home user, or to a WSUS server on a
managed network, or via Windows or MicrosoftUpdate.
DKI laid out as well as I can what you need to do to attempt to clear this
issue up and get updates back to being applied automatically--can you try
his steps?
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