HomeWinBuzzer NewsWindows 11 Cumulative Update is Causing BSOD Errors

Windows 11 Cumulative Update is Causing BSOD Errors

It seems a broken Sophos driver is causing BSOD errors on Windows 11 following an update. There is now a fix available.


's newest cumulative update for is causing issues for users. Seemingly caused by bad drivers, the release is causing BSOD (black/blue screen of death) errors. According to security firm Sophos, the drivers come from its antivirus software.

This explains why some Windows 11 devices are affected by the BSOD error. In other words, PCs that have the affected Sophos drivers installed. This means Microsoft is not to blame this time.

“Customers on Windows 11 running Sophos Home may encounter a BSOD/Stop error after installing KB5013943 and restarting their machines. The symptoms involve being unable to get to the desktop after restarting the computer/shutting down powering it back on post installation of Windows Update KB5013943. This includes a Stop Error Index Mismatch message (Blue Screen),” Sophos says.

Sophos has reacted quickly to the issue and announced a fix, while there are also two workarounds available for the problem. Of course, the fix is the better option, but if you cannot install that fix for whatever reasons, the workarounds can also help.


These workarounds focus on essentially removing the Windows 11 cumulative update (KB501943) entirely or renaming the hmpalert.sys driver on Windows 11.

Still, the fix is the best course of action, although you'll need to be running version to get it. Below are the full instructions for installing the fix:

  1. “Users will receive a Restart Required message in Sophos Home as soon as the automatic fix is installed
  2. Open Windows Explorer and navigate to C:\Windows\System32\drivers
  3. Locate hmpalert.sys > Right-click > Properties> Details
  4. Confirm the Product version is”

Tip of the day: For the most part, Windows apps are stable, but they can still be still thrown out of whack by updates or configuration issues. Many boot their PC to find their Microsoft Store isn't working or their Windows apps aren't opening. Luckily Windows 11 and have an automatic repair feature for apps that can resolve such issues.

Luke Jones
Luke Jones
Luke has been writing about all things tech for more than five years. He is following Microsoft closely to bring you the latest news about Windows, Office, Azure, Skype, HoloLens and all the rest of their products.

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