How to Fix Error DRIVER IRQL NOT LESS OR EQUAL (kbdclass.sys) in Windows 10


Zerrows.com - Some PC users are experiencing unusual problems with their wireless keyboards. This problem occurs on Microsoft wireless keyboards. When they plug in a standard wired USB keyboard, they can use a Windows 10 computer. Still, when the wireless keyboard is plugged in, and any keyboard key is pressed, the computer crashes and displays the Blue Screen of Death error DRIVER_IRQL_NOT_LESS_OR_EQUAL (kbdclass .sys). This article will discuss this error and provide the most suitable solution for this problem.

KBDCLASS.SYS is a Keyboard Class classified as a driver. It is responsible for the general settings on the keyboard. This driver handles all keyboard key combinations as well as all single keys you press on the keyboard.

All versions of Windows have a unique code assigned to them. If the output class isn't a file system, then you probably shouldn't have a problem. However, in this critical case, the .sys file is the system file. Accordingly, if the code of this class is changed in any way, KBDCLASS.SYS will crash and consequently will trigger BSOD errors and other problems.

Fixed Error DRIVER_IRQL_NOT_LESS_OR_EQUAL (kbdclass.sys)

If you are faced with this problem, you can try the solutions I recommend below in no particular order and see if they help you solve the problem with this error.

If you can log in normally, then that's great. But if not, you'll need to boot into Safe Mode, enter Advanced Startup Options, or use the Installation Media to boot to run these instructions.

1. Uninstall Third-Party Antivirus Software

Errors are a general problem caused by Webroot antivirus. In other words, the problem arises because of a conflict between the wireless keyboard driver and the Webroot software. In this case, to resolve the issue, make sure you are running the latest version of the Webroot antivirus, as Webroot is aware of the problem and has created and released a patch for it.

However, suppose the problem is still not resolved. In that case, you should uninstall a third-party antivirus program from your PC using a special uninstaller tool to delete all files related to Webroot antivirus because some users uninstalled Webroot from their Windows 10 PC are still affected by the BSOD error. So, it's much more efficient and invasive to use the manufacturer's dedicated AV program uninstaller tool (if available) every time you want to uninstall antivirus software because there are registry and dependencies installed deep in the OS where the traditional Control Panel uninstaller (appwiz .cpl) is. I might miss it in most cases.

2. Update Drivers

Corrupt or outdated drivers can trigger this BSOD error as well.

In this case, you can update your drivers manually via Device Manager or you can get driver updates in the Optional Updates section under Windows Update or use the driver update tool. You can also download the latest version of the driver from the manufacturer's website.

3. Keyboard Driver Rollback

Suppose Windows automatically installs an update for your HID Keyboard Device, and the update automatically changes the keyboard class code. In that case, this can cause the error to appear.

In this case, you can restore the HID Keyboard driver under the Human Interface Devices section of Device Manager and see if that helps.

4. Reinstall USB Controllers

To reinstall USB Controllers, you must first uninstall them. After that, restart the system, and the USB Controllers will be reinstalled automatically. To uninstall USB Controllers, follow these steps.

  • Press Win + X keys and select Device Manager from the list.
  • Once you are in the Device Manager, scroll down to the Universal Serial BUS Controllers section and expand that section.
  • Right-click on Generic USB Hub and select Uninstall device.

  • Do the same for the USB Root Hub entry.
  • After everything is uninstalled, restart your computer.

The problem should be solved now. If not, continue with the next solution.

5. Perform a System Restore

This procedure is very effective in solving most problems in Windows 10, including BSOD errors like this one. You can restore your system to a previous point. This will restore your system to an earlier point when the system is still functioning correctly.

You can also read my other articles on the best way to fix the Blue Screen of Death error in Windows 10 and see more options for fixing this error if the above methods work.

That's it for this tutorial. I hope it helps you. Don't forget to leave your comments below to share your experiences following this tutorial. Thank you.