Windows 10: Windows Defender will not remove or quarantine a threat that is over 30 days old

On 1 July 2020 Windows Defender claimed to have detected a low rated threat called

PUA.Win32.DownloadSponsor
but Windows Defender will not remove or quarantine it and is still detecting the threat although I am unable to find it on my computer. Windows Defender also says:


Affected items:

containerfile: G:\Downloads\unipdf1.4.exe

file: G:\Downloads\unipdf1.4.exe->[lowcase_mzpe]


I have rigorously searched my computer and have been unable to find any file with that name. I have no idea what [lowcase_mzpe] means.

I have tried some of the Trend Micro approaches https://www.trendmicro.com/vinfo/my/threat-encyclopedia/malware/pua.win32.downloadsponsor.ap to get rid of the file but they do not work. I have also scanned with HitmanPro, Malwarebytes, SuperAntispyware, and the EMSI Emergency kit, but none of them even detect it.


Does anyone know how to get rid of the problem?

:)

 

quarantined threats

In the Windows Defender Security Center, the Quarantined Threats list on the Scan History page corresponds to the Quarantined Items page in the classic UI, and that list will display any items that have actually been quarantined,
as well as provide the options to remove or restore any of those items – as we can see in this screenshot:





You can either click on the Remove all button or click on a down arrow in order to display the option buttons for an individual threat. But remember that the recommended action can sometimes be wrong when a harmless file is quarantined
by mistake (a false positive), and that's the reason why threats are quarantined rather than removed automatically. The items in the Quarantine could be safely left there indefinitely; but they'll be automatically removed after 90 days, by default.

The number of days that the item is kept in the Quarantine can be reconfigured with this preference setting:

-QuarantinePurgeItemsAfterDelay

Specifies the number of days to keep items in the Quarantine folder. If you specify a value of zero for this parameter, items stay in the Quarantine folder indefinitely.

https://docs.microsoft.com/en-us/powershell/module/defender/set-mppreference?view=win10-ps

For example, to have quarantined items automatically removed after just a week, run this command at the Administrator PowerShell prompt:

Set-MpPreference -QuarantinePurgeItemsAfterDelay 7

 

How do I remove quarantined threats

It does say under 'Quarantined threats' that "Quarantined threats have been isolated and prevented from running on your device. They will be periodically removed". It could just be that by now they have been automatically removed. It's a possibility as your detections were a few days ago on the 5th. My test was less than 24 hours ago so the quarantined file has not (yet) been automatically removed.

Just reassurance that it's working as designed.

 

Windows Defender is missing Restore Button for Quarantined Threats

It wasn't listed under "Quarantined Threats", but was listed in "See full history" as quarantined. It has been about 2 hours
and now it is listed under "Quarantined Threats" which now shows the Restore or Delete options. Something must be causing
a delay in listing the quarantined file under "Quarantined Threats" after they have been found and quarantined by Defender.