“The oldest and strongest emotion of mankind is fear, and the oldest and strongest kind of fear is fear of the unknown.”

-H.P. Lovecraft

Blue Screen of Death errors can be dreadful, especially when you don’t know how to deal with them. Fortunately, there are solutions to most of them, including the DRIVER_IRQL_Not_Less_Or_Equal (Mfewfpk.sys) error. In most cases, when this issue comes up, the computer crashes. It will show a blue screen with a message which says that the operating system has been shut down to prevent further damage. The message will also say that the error was caused by the Mfewfpk.sys file.

If you’re experiencing the same dilemma, do not worry. In this post, we will teach you how to fix the DRIVER_IRQL_Not_Less_Or_Equal (Mfewfpk.sys) BSOD on Windows 10. We understand that this problem can prevent you from upgrading your operating system to the latest version. In some cases, it may even keep you from using your PC entirely. We know how frustrating this can be. As such, we have put together this article to show you the various guides on how to resolve the DRIVER_IRQL_Not_Less_Or_Equal (Mfewfpk.sys) Windows 10 error.

What Causes the DRIVER_IRQL_Not_Less_Or_Equal (Mfewfpk.sys) BSOD Error?

SYS files are critical data necessary for the proper function of various third-party software. In some cases, they come in the form of kernel mode device drivers that play an important role in the Windows operating system. It is worth noting that Mfewfpk.sys is the driver that is crucial for the operation of McAfee Total Protection.

Usually, the BSOD error shows up when users with McAfee products try to upgrade from Windows 8.1 to Windows 10. Once they try to reboot their system, they will get stuck with the DRIVER_IRQL_Not_Less_Or_Equal (Mfewfpk.sys) BSOD error. Basically, an issue with the Mfewfpk.sys file prevents the user from upgrading their operating system successfully. That said, this issue can be resolved. You can learn how to fix the DRIVER_IRQL_Not_Less_Or_Equal (Mfewfpk.sys) BSOD on Windows 10 from this article.

Solution 1: Removing McAfee

As we’ve mentioned, the root cause of the issue is the Mfewfpk.sys file, which is the driver for McAfee Total Protection. So, we recommend that you remove this anti-virus software, then try upgrading your operating system again. You can uninstall the program by downloading the McAfee Consumer Products Removal Tool online. On the other hand, you can also delete the anti-virus via Control Panel. If you’re using Windows 8.1, follow the steps below:

  1. Go to your taskbar, then right-click the Windows icon.
  2. Select Programs and Features from the list.
  3. Now, look for the McAfee program you want to delete.
  4. Select the program, then click Uninstall at the top of the list.
  5. Follow the on-screen instructions on removing the anti-virus.

McAfee has been known to develop faulty codes in the past. So, you are better off without it. However, it is still important that you have adequate protection against threats and viruses. In this case, we recommend that you use Auslogics Anti-Malware. Since this tool was created by a certified Microsoft Silver Application Developer, it will not interfere with any Windows process. You can rest assured that it will not cause BSOD errors when you try to upgrade your operating system. What’s more, you can expect it to detect malicious items no matter how complex or discreet they are.

Solution 2: Booting Your System in Safe Mode

Another way to resolve the BSOD error is to boot your system in Safe Mode. Here are the steps:

  1. Press and hold the Shift key, then click the Power button.
  2. Choose Restart, then click Troubleshoot.
  3. Select Advanced Options, then choose Startup Settings.
  4. Click Restart.
  5. Once the system boots, choose Enable Safe Mode with Networking.

Now, check if the OS starts without the DRIVER_IRQL_Not_Less_Or_Equal (mfewfpk.sys) error. If so, follow the steps below to perform a clean boot:

  1. On your keyboard, press Windows Key+R.
  2. Inside the Run dialog box, type “msconfig” (no quotes), then click OK.
  3. Once the System Configuration window shows up, go to the Services tab.
  4. Make sure that the ‘Hide all Microsoft services’ option is selected.
  5. Click Disable All to remove all third-party services from the startup list.
  6. Now, go to the General tab.
  7. Click the Selective Startup option, then deselect the ‘Load startup items’ checkbox.
  8. Close the System Configuration window, then restart your computer.

Solution 3: Performing an SFC Scan

Since you’re dealing with a corrupted or damaged SYS file, you can perform an SFC scan to resolve the problem. To do that, follow the instructions below:

  1. Right-click the Windows icon on your taskbar.
  2. Select Command Prompt (Admin) from the options.
  3. Once Command Prompt is up, run these commands one by one:

chkdsk /f

sfc /scannow

Once the processes are complete, check if the issue has been resolved.


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What other BSOD errors would you like us to discuss?

Feel free to ask your questions in the comments below!