Troubleshoot Windows Defender or Endpoint Protection client

Applies to: Configuration Manager (current branch)

If you come across problems with Windows Defender or Endpoint Protection, use this article to troubleshoot the following problems:

Update Windows Defender or Endpoint Protection

Symptoms

Windows Defender or Endpoint Protection works automatically with Microsoft Update to make sure that your virus and spyware definitions are kept up-to-date.

This section addresses common issues with automatic updates, including the following situations:

  • You see error messages indicating that updates have failed.

  • When you check for updates, you receive an error message that the virus and spyware definition updates can't be checked, downloaded, or installed.

  • Even though your device is connected to the internet, the updates fail.

  • Updates aren't automatically installing as scheduled.

Causes

The most common causes for update issues are problems with internet connectivity. If you know your device is connected to the internet because you can browse to other Web sites, the issue might be caused by conflicts with your internet settings in Windows.

Options to resolve

Step 1: Reset your internet settings

  1. Exit all open programs, including the web browser.

    Note

    When you reset these internet settings, it may delete your browser temporary files, cookies, browsing history, and online passwords. It doesn't delete your favorites.

  2. Go to the Start menu, and open inetcpl.cpl.

  3. Switch to the Advanced tab.

  4. In the section to Reset Internet Explorer settings, select Reset, and then select Reset again to confirm.

  5. Select OK when the settings are reset.

  6. Try to update Windows Defender again.

If the issue persists, continue to the next step.

Step 2: Make sure that the date and time are set correctly on your computer

If the error message contains the code 0x80072f8f, the problem is most likely caused by an incorrect date or time setting on your computer. Go to the Start menu, select Settings, select Time & language, and select Date & time.

Step 3: Rename the Software Distribution folder on your computer

  1. Stop the Windows Update service.

    1. Go to Start, and open services.msc.

    2. Select the Windows Update service. Go to the Action menu, and select Stop.

  2. Rename the SoftwareDistribution directory.

    1. Open a command prompt as an administrator.

    2. Enter the following commands:

      cd %windir%
      ren SoftwareDistribution SDTemp
      exit
      
  3. Restart the Windows Update service.

    1. Switch back to the Services window.

    2. Select the Windows Update service. Go to the Action menu, and select Start.

    3. Close the Services window.

Step 4: Reset the Microsoft antivirus update engine on your computer

  1. Open a command prompt as an administrator.

  2. Enter the following commands:

    cd \
    
    cd program files\windows defender
    
    MpCmdRun -RemoveDefinitions -all
    
    exit
    
  3. Restart the computer.

  4. Try to update Windows Defender again.

If the issue persists, continue to the next step.

Step 5: Manually install the definition updates

Manually download the latest updates.

Step 6: Contact Microsoft support

If these steps didn't resolve the issue, contact Microsoft support. For more information, see Support options and community resources.

Starting Windows Defender or Endpoint Protection service

Symptom

You receive a message notifying you that Windows Defender or Endpoint Protection isn't monitoring your computer because the program's service stopped. You should restart it now.

Solution

Step 1: Restart your computer

Close all applications and restart your computer.

Step 2: Check the Windows service

  1. Go to Start, and open services.msc.

  2. Select the Windows Defender Antivirus Service.

  3. Make sure that the Startup Type is set to Automatic.

  4. Go to the Action menu and select Start.

    1. If this action isn't available, select Stop. Wait for the service to stop, and then select the Start action to restart the service.

Note any errors that may appear during this process. Contact Microsoft Support and provide the error information.

Step 3: Remove any third-party security programs

Note

Some security applications don't uninstall completely. You may need to download and run a cleanup utility for your previous security application to completely remove it.

  1. Go to Start and open appwiz.cpl.

  2. In the list of installed programs, uninstall any third-party security programs.

  3. Restart your computer.

Caution

When you remove security programs, your computer may be unprotected. If you have problems installing Windows Defender after you remove existing security programs, contact Microsoft Support. Select the Security product family, and then the Windows Defender product.

Internet connection issues

For your computer to receive the latest updates from Windows Update, connect it to the internet.

  1. Go to Start and open ncpa.cpl.

  2. Open the connection name to view the connection Status.

  3. If your computer is connected, the IPv4 connectivity and/or IPv6 connectivity status is Internet.

  4. If your computer doesn't appear to be connected, select the connection name, and select Diagnose this connection.

Close any open programs and restart your computer.

Detected threat can't be remediated

When Windows Defender or Endpoint Protection detects a potential threat, it tries to mitigate the threat by quarantining or removing the threat. These threats can hide inside a compressed archive (.zip) or in a network share.

Remove or scan the file

  • If the detected threat was in a compressed archive file, browse to the file. Delete the file, or manually scan it. Right-click the file and select Scan with Windows Defender. If Windows Defender detects additional threats in the file, it notifies you. Then you can choose an appropriate action.

  • If the detected threat was in a network share, open the share, and manually scan it. Right-click the file and select Scan with Windows Defender. If Windows Defender detects additional threats in the network share, it notifies you. Then you can choose an appropriate action.

  • If you're not sure of the file's origin, run a full scan on your computer. A full scan may take some time to complete.

See also

Endpoint Protection client frequently asked questions

Endpoint Protection client help