How to Repair: Error Code 0x80016CFA in Windows Defender

Some Windows users have contacted us with questions after constantly getting pop-up windows with the error code: 0x80016CFA when trying to open a new page in the browser. This has been confirmed to occur in Edge, Internet Explorer, Opera, Chrome, and some other third-party browsers.

If you see this type of pop-up when you open your default browser, your computer is likely infected with adware that has effectively taken over your browser. In most cases, this is made possible by a browser hijacker that security researchers call ‘Rogue Tech-Support-Scam’.

What causes Windows Defender error code 0x80016CFA?

It’s the tech-support scam that aims to trick users into calling a toll-free support number for help. When they do, they are greeted by people claiming to represent Microsoft and trying to extort money from them.

So if you see this error message on your browser, DO NOT call the toll-free number. Instead, you should follow a series of instructions to remove this adware from your computer so that the pop-ups do not appear again. Depending on the type of malware you are dealing with, there are several ways to resolve this problem.

In most cases, you have let the malware infect your computer after clicking a link or opening an email attachment.

How to resolve the Windows Defender error code 0x80016CFA?

Remove/Uninstall the faulty application

If you encounter Windows Defender error code 0x80016CFA after installing a certain application, it is possible that the newly installed application is corrupted. In this case, we recommend uninstalling the application, as simply deleting corrupted files is not enough.

If you delete corrupted files but do not remove the application, there is a high risk that the program will reinfect your system.

  1. Run the Run dialog box by pressing the Windows + R keys at the same time.
  2. Type `appwiz.cpl` in the text box and press Enter. The “Programs and Features” window will open.
  3. Now find the suspicious program and right-click on it.
  4. Click Uninstall and follow the instructions on the screen to remove the application.

Remove the unwanted extensions and restart your web browser

One of the most common causes of Windows Defender error code 0x80016CFA is a browser corruption error. This can be caused by several reasons, including faulty browser extensions and add-ons.

If your browser displays error code 0x80016CFA, the first thing you should do is remove the suspicious extensions and then reload the web browser. The steps may differ depending on the browser you are using, but the basic principle is the same.

  1. Open your web browser and click the Plus button (three dots) in the upper left corner.
  2. If you’re using Google Chrome, select “Other Tools” and click on “Extensions”.
  3. For Microsoft Edge, you will find the Extensions option right after clicking on the Plus button.
  4. Now find the suspicious extension and click the Uninstall button.
  5. Then go to Settings by clicking the More button.
  6. In the left pane of the browser, find the On Startup option and click on it.
  7. Select Open specific page(s) and click Use current pages.
  8. Select the suspicious pages you want to remove and delete them.
  9. Now click on Add New Page and select the page you want to use as your browser’s home page.
  10. Then go back to Settings and select Reset Settings.
  11. Wait for the process to complete.
  12. Then check to see if the error has been fixed.

Frequently Asked Questions

  1. Reboot your computer.
  2. Uninstall any existing antivirus and antispyware programs.
  3. Scan your computer for malware.
  4. Scan for SFC.
  5. Clean start.
  6. Restart the Security Centre service.
  7. Remove conflicting registry entries.
  8. Enable Windows Defender using Group Policy.

  1. Go to the Start menu and open the Control Panel.
  2. Click on the Windows Defender tab and select Restore Defaults on the left.
  3. Click Restore Defaults and confirm your action by clicking Yes in the confirmation window.

If you want Windows Defender to work, you must uninstall third-party security software and reboot your system. Type "Windows Defender" in the search box and press Enter. Click Settings and make sure the Enable real-time protection option is checked.

If Windows Defender is disabled, it may be because you have another antivirus application installed on your computer (check Control Panel, System and Security, Security and Maintenance to make sure). You should disable and uninstall this application before running Windows Defender to avoid software conflicts.