Windows 10: Window defender reported a Trojan threat but couldn't take action

My Window defender detected a threat that is named Trojan:Win32/Tnega!MSR this morning. I tried taking action quarantine and remove but nothing happened, the threat was still there I checked the protection history and it's still the same. However, when I tried quick scan again the notification told me that there was no threat detected as picture but when I check my window defender the threat is still there.I did try restarting and using many anti-virus software but they all reported no threats except Window defender. Aside from that, I checked my computer's files and didn't find any susp

:)

 

Windows defender false positive - forced to allow threat

Windows defender has started to identify C:\Windows\System32\mshta.exe as a threat [normally reported as a Trojan Powessere.G]. I use mshta.exe to run an hta custom MsgBox - I have been hoping to keep using my current CustomMsgBox tool [batch file calling a vbs-hta file] until later this year when I hope to have had enough time to replace it with a PowerShell alternative.

Windows defender's notification lets me "allow the threat" but that seems to me to be a bigger security hole than is necessary - it will now ignore a potentially real intrusion when all I want to run is a genuine Windows component. My immediate problem is fixed but I would prefer to fix the false positive using the exclusions list.

I cleared the 'Allowed threats history' so I could use the exclusions list instead. I added C:\Windows\System32\mshta.exe to the file exclusions list and I checked that it had taken properly by checking the exclusions list both in the UI & in the Registry. But the exclusion made no difference, it continued to detect and block the exe.

I have repeated the attempt several times [by clearing the allowed threats list & exclusions list beforehand] and the results are the same every time
- allowing the threat works,
- using the exclusions list has no effect.

I studied the relevant tutorial but have not spotted an error in what I have been doing - Add or Remove Windows Defender Exclusions

Does anybody with experience of using the exclusions list to counter false positives have any suggestions for me?

Denis

 

Action centre repeatedly reports "Threats found" but Defender disagrees and says everything is fine.

I'm getting same problem....only since Creator's update.

Action centre repeatedly reports "Threats found" but Defender disagrees and says everything is fine.

I tried the fix above but it still happens.

Any suggestions?

 

Security from overload of virus threats

Repeating threat detections often mean that Windows Defender just wasn’t up to the task of removing the malware that it detected. Sometimes you can complete the removal process with something as simple as running a scan with Windows Defender Offline.
You can query Windows Defender for any additional actions that might be needed by running the PowerShell
Get-MpThreatDetection command, and then examining the value of the Additional Actions Bitmask:

https://answers.microsoft.com/en-us...as-found/e40c5309-d2a1-437a-b205-75c6bc7e77ca

In many cases, though, you’ll need to run a scan with a third-party malware-removal app in order to complete the malware-removal process. For example, many of the repeated detections that we’ve been seeing lately are for Trojan:HTML/Brocoiner!rfn.
This Beeping Computer thread suggests that just scanning with Malwarebyes in Safe Mode might be sufficient for the removal of this threat:

Infected with TROJAN: HTML/BROCOINER!RFN - Virus, Trojan, Spyware, and Malware Removal Help

Note the references to Rootkit.Fileless.MTGen in the detections.

If scanning with Malwarebytes doesn’t stop the notifications; then follow the steps in this guide, which can be applied to other threats in addition to Trojan:HTML/Brocoiner!rfn:

https://malwaretips.com/blogs/remove-trojan-html-brocoiner/