Windows 10: Windows Defender is not working

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Not working.


What I was trying to resolve this issue.


1. Remove Hyper-V

2. Install 3rd party software to clean PC. Avast, Malwarebytes, ...

3. Add DisableAntiSpyware DWORD to registry

4. Start in Safe mode

5. sfc /scannow

6. Uninstall latest quality updates, functional updates this doesn't work, it shows me only that some error occured

7. Check EventLog for any Error about the windows defender


Till yesterday everything works fine, today when I start windows the shield icon just appear for a while with warning and dissapear.

And due to this problem I was unable to use Hyper-V any more, because it is keeps disconnecting my internet constantly.


So, it has to be something with windows, not 3rd party softwares installed on my desktop

:)

 

Windows Defender Not Working in Windows 10

Hi,

Thank you for using Windows 10.

Sorry for the delayed reply. I suggest you to 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.
• Search for Windows defender.
• Double-click Windows Defender, and click Automatic in the start-up box > click OK.

Also, follow the below mentioned steps and check:

• Open the Task manager. Here’s a tip: Press CTRL+Shift+ESC.
• Click File > Run New Task
• Make sure you have a check mark beside “Create this task with administrative privileges”
  
• Type CMD
• Type the following 2 commands at the CMD prompt:
  
  dism /online /cleanup-image /restorehealth
  
  sfc /scannow
  
  
• Close the CMD window

Keep us posted on the status of the issue and we’ll be glad to help.

 

Windows Defender Not Working in Windows 10

Hello,

Thank you for keeping us posted on the status of the issue.

We appreciate your patience on this issue. I would like to assist you further on this issue.

Error 577 Windows Defender error codes are caused in one way or another by misconfigured system files in your windows operating system, which may be caused by windows system files damage.

Please be informed that In order for Windows Defender to run, it will require that the
Windows Defender Service remain "Started" (running) and set to "Automatic". Also, certain 3rd party antivirus programs are mainly responsible as it turns off the Windows Defender when they are installed.

Please follow the below methods.

Method 1

This issue may happen due to system file corruption. I suggest you to run System file checker. System File checker (SFC) scan is done to check if there are any corrupted system files that could be causing this issue. Kindly follow
the below given steps:

• 
  Press Windows key + X, select
  Command prompt (Admin) to bring up elevated Command prompt.
  
• 
  In Command prompt type
  sfc/scannow and press enter.
  
• 
  Restart the computer.
  
  If no corrupted system files were found in the previous state, then I suggest you to try the following steps:
  

• 
  Open command prompt by pressing Windows key + X and selecting “Command prompt admin”.
  
• 
  In command prompt, type the following commands and press Enter after each command:
  
  DISM.exe /Online /Cleanup-image /Scanhealth
  
  DISM.exe /Online /Cleanup-image /Restorehealth
  

• 
  Close the command prompt and restart the PC and check if it works.
  

Method 2

Please follow the below steps to set the right registry entry and check if it helps.

• Press Win key + R. This will open Run.
• Type "regedit" and hit enter.
• Navigate to these keys:
  
  HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\Windows Defender
  
  HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows Defender
• Change value of 'DisableAntiSpyware' and 'DisableAntiVirus' from '0' to '1'.
• After changing the values go to 'C:\Program Files\Windows Defender' and open 'MSASCui.exe' file.

Hope the above information was helpful. If you need further information, feel free to write to us and we would be happy to help you.

Thank You.

 

Windows Defender Not On

Hi,



Welcome to Microsoft Community. Your interest in Windows 10 is much appreciated.



I would suggest you to try the below methods and check:

Method 1:

I would suggest you to run virus scan to make sure the computer is free from virus.

The Microsoft Safety Scanner is a free downloadable security tool that provides on-demand scanning and helps remove virus, spyware, and other malicious software. It works with your existing antivirus software.

Microsoft Safety Scanner Download - Windows security



Method 2:

Turn the Defender on. Follow the below steps:

• In search, type Defender.
• Now make the option ON by moving the slider accordingly.

Method 3: Run the SFC.

Follow the below steps:

• Open Command Prompt.

• Select “Run as Administrator”.
• Type “sfc /scannow” without quotes and hit
  Enter.

Now check for the issue.



Keep us posted if you face any issues on windows in future. We will be glad to help you.