Windows Defender: None of the scan options work

OldGrantonian · 09 Dec 2020

I have Win 10 Pro 2004.

Windows Defender and MalwareBytes Premium are "always on". I ran a MB scan just now - nothing found.

If I click Scan Now in the Win Defender dialog, nothing happens. None of the options work. The dialog simply remains open - as if the button was never pressed. I noticed this when I tried to scan a file by using the right-click context menu. The option is no longer available.

I used one of the Brink's tutorials to install:

Add_Scan_with_Microsoft_Defender_context_menu.reg

The patch was successful.

Please advise.

Thanks.

FreeBooter · 09 Dec 2020

See if re-registering Windows Security App works.

OldGrantonian · 09 Dec 2020

FreeBooter said:

See if re-registering Windows Security App works.

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Thanks, but Windows does not allow either opening or saving that file.

Maybe you could rename it to TXT or something? I'll rename it back to BAT.
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FreeBooter · 09 Dec 2020

Open the Command Prompt as a administrator and execute below command.

Code:

PowerShell -ExecutionPolicy Unrestricted -Command "& {$manifest = (Get-AppxPackage *Microsoft.Windows.SecHealthUI*).InstallLocation + '\AppxManifest.xml' ; Add-AppxPackage -DisableDevelopmentMode -Register $manifest}"

OldGrantonian · 10 Dec 2020

FreeBooter said:

Open the Command Prompt as a administrator and execute below command.

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I ran the script as instructed.

That had no immediate effect. But on restart, the context menu option was available.

I tested by selecting a file to scan.

I got the message: "Page not available. Your IT Admin has limited access to this app....Contact IT helpdesk.

The context menu disappeared again.

BTW: All the above was done using an account with Admin privileges (not the account named "Administrator" - which I try to avoid using.)

Thanks.

FreeBooter · 10 Dec 2020

You can use attached batch script to reset local group policy settings.

OldGrantonian · 10 Dec 2020

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Thanks for the script, but as I mentioned previously I'm not allowed to open or save these scripts.

FreeBooter · 10 Dec 2020

How come what is blocking you from executing the batch scripts?

OldGrantonian · 10 Dec 2020

When I click on the script, I see the following options:

Windows Defender: None of the scan options work-image.png

If I select Open, I see the following:

If I delete that message, and select Save As, I'm presented with a File Explorer dialog to select a target. But as soon as I select Desktop, I get the message shown in second screenshot above.

BTW: On reflection, I've downloaded dozens of REG files from Brink's tutorials. Some of these are still visible. So something has changed in my laptop.

I haven't done a context scan - or downloaded any of Brink's stuff - for several months, so the problem could have been present for months.

Thanks.

- - - Updated - - -

.
I've cracked this issue.

MalwareBytes was silently turning off Windows Defender.

I have no idea when this happened, because - as I mentioned above - it's a long time since I had to scan a download using the file context menu.

The whole story is here:

Fix: Malwarebytes Disables Windows Defender or 3rd Party Anti-Virus >> Winhelponline

This not necessarily the "best" link - it's simply the first reasonable entry that appeared in Google.

I'm a long-time big fan of MB, but I think it's f___ rude to silently interfere in something as important as AV without the courtesy of a notification.

BTW: I was aware that the MB block of text was replacing the scan options in the Win Defender dialog, but I was too dumb to figure out why. (See the screenshot in the above link.)

EDITED: Anyway, thanks to @FreeBooter for ~~his~~ [INS]their[/INS] generous efforts to help. [INS]Apologies[/INS]
.

Paul Black · 10 Dec 2020

Hello @OldGrantonian,

OldGrantonian said:

When I click on the script, I see the following options:

If I select Open, I see the following:

If I delete that message, and select Save As, I'm presented with a File Explorer dialog to select a target. But as soon as I select Desktop, I get the message shown in second screenshot above.

BTW: On reflection, I've downloaded dozens of REG files from Brink's tutorials. Some of these are still visible. So something has changed in my laptop.

I haven't done a context scan - or downloaded any of Brink's stuff - for several months, so the problem could have been present for months.

As a workaround in the future if you have problems, you could always copy the code into Notepad and save it as a .bat file and then run it. If somebody asks you to run a particular Batch file, they are more than likely inclined to also post the actual code for you as well in order for you to create your own Batch file and run it!

I hope this helps!