Windows 10: Defender Antimalware windows update-corrupted SFC scan is back again

After using DISM to fix the recent Windows Defender Platform corruption found when running an sfc scan. Tonight Windows Update has installed the latest version of the Windows Antivirus Defender Antimalware Platform KB405263 version 4.18.1907.4 and to check if it was still OK... I ran SFC/ Scannow again. Unbelievably the corruption is back! I now don't have a clue whether to leave it alone or fix it again

:)

 

Defender antimalware client update

I've learned to live with it. It just seems odd that the exact same task doesn't work the same on different machines, when it used to. Just witnessed it again. One computer ran the scan as it should, the other did not. It started with the CU so maybe the next update will fix it, but I won't hold my breath.

 

Defender antimalware client update


Bru,

Sorry I confused things then.

I found another thread of yours [Schedule Scan in Windows Defender Antivirus.

• That being the case, you'll have the tasks' various properties [General, Triggers, Actions, Conditions, Settings] set up the same way on each computer. If all the computers are at Ver 1709 then I expect the Action tab to show

C:\ProgramData\Microsoft\Windows Defender\platform\4.12.17007.18011-0\MpCmdRun.exe Scan -ScheduleJob -ScanTrigger 55but the '55' can vary.

• Might I suggest that you click on All tasks history [on the right-hand side of the Task scheduler window] so that Task scheduler collects records of scanning attempts

• Can you describe the differing behaviour of each computer's task
  • 1 in terms of the symptoms you see as a user, and
  • 2 as they appear in each task's History tab [note that you will have to double-click on each task as if you were going to edit it just in order to adjust the column widths of the History tab entries so you can see them properly - it's a real pain because you'll have to do the same again the next time you want to look at the History], and
  • 3 as they appear in the Windows Defender log at

%UserProfile%\AppData\Local\Temp\MpCmdRun.log {you can just paste the whole path & filename into File explorer to get straight there}.
Denis

 

Windows Defender not completing scans

Hi,

Thank you for posting your query on Microsoft Community.

As per the description, I understand that you are facing issues using Windows Defender.

I would suggest you to go through the below methods:

Method 1: Set Windows Defender to Automatic

You can set the Windows Defender service to Automatic, Disabled or Manual. Setting it to automatic might solve the problem. Follow these steps:

• 
  Click Start > type services in the Search box > click Services in the Programs list.
  
  2. Search for Windows defender.
  
  3. Double-click Windows Defender, and click Automatic in the start-up box > click OK.
  
• 
  

Method 2: Run SFC scan, it will check, if there is any kind of corruption on the operating system.

• 
  Press WIN+X.
  
• 
  Click on command prompt with admin.
  
• 
  Type sfc /scannow and press enter.
  
• 
  Reboot the computer once finished.
  

Method 3: Try the below link:

https://support.microsoft.com/en-us/kb/931849

Hope this information helps. Please let us know if you need any other assistance with Windows in future. We will be happy to assist you.