Windows Defender error code 0x80040201 is a malicious error that occurs with a pop-up message “ BSOD: DllRegisterServer Failed ” (BSOD stands for Blue Screen of Death).

You are most likely to encounter this error after opening an infected website which generates fake warnings and alerts on your screen. 

Furthermore, they also promise you an apparent fix by providing this one bogus contact number which is most likely to produce nothing but a bill of unexpected amount.

Basically, it is a scam by crooked websites to steal your money through online transactions. However, if you have been experiencing this pop up as well, then do not worry. As we are going to discuss some of the easy tricks to get rid of it without any trouble. 

Follow the segment summoned below for more information.

Easy Tricks to Fix Windows Defender Error Code 0x80040201 Popup on Your Screen

It is extremely important to be cautious while visiting unknown websites, as they are the ones that cause damage. Thus, make sure to run a full PC scan with prominent antivirus tools first. 

If the problem still persists, we have mentioned some simple methods to get rid of Windows Defender Error Code 0x80040201 popup on your system.

For Windows

To fix the malicious code on your Windows system, follow the steps cited below.

  • Go to Start and type Control Panel on the search bar. 
  • Click on “Uninstall a Program” and go through the installed programs displayed in a list.
  • Spot the suspicious ones and uninstall them.

For macOS

If you have been experiencing this error on your macOS then you need to follow the steps given below thoroughly.

  • Click on Go>Finder> Applications.
  • Look for programs that seem suspicious to you and right-click on each of them.
  • After doing so, transfer them to the Trash.

Clean Your Internet Browser

Another process by which you will be able to fix this error code is by resetting your browser to the default settings. Here, we have listed the reset procedure for Google Chrome, Mozilla Firefox, Internet Explorer, and Safari in sequence.

Google Chrome

  • Firstly, open Google Chrome and then select the menu option. Click on the Settings> Advanced.
  • Go to the bottom of the page and select the “Reset settings to their original defaults” option.
  • Now close the recently opened tab and relaunch Google Chrome. 

Mozilla Firefox

  • Go to the Firefox menu and locate the Help area. Select the Troubleshooting Information option within the drop-down menu of Help.
  • Click on the “Reset Firefox” option and then confirm it by clicking on the “Reset Firefox” button located within the pop-up window.

Internet Explorer

  • Navigate to the Internet Explorer menu and click on Tools. After that, go to Internet options and then the Advanced tab.
  • Click on the Reset option, present within the Reset Internet Explorer Settings section.


  • Launch Safari and then go to the Safari menu. Now, navigate to Preferneces>Extensions.
  • Look for questionable entries and uninstall them individually.
  • Go to the General tab and then check the URL that is set as a homepage. If you notice that it has a suspicious link in it, then replace it with a website according to your preference. (http:// should be typed before the URL)
  • Reset Safari by clicking on Safari and then selecting the “Reset Safari….” option on your screen.
  • Check all the boxes once the Reset Safari pop-up appears.

So these were are some of the simple techniques by which you should be able to resolve the Windows Defender error code 0x80040201 popup without any difficulty. Please let us know your experience in the comment section below.