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Fix: DRIVER_IRQL_NOT_LESS_OR_EQUAL (kbdclass.sys) BSoD

More often, corrupt system files prompts this BSoD error

5 min. read

Updated onMarch 29, 2024

updated onMarch 29, 2024

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Key notes

Kbdclass.sys or DRIVER_IRQL_NOT_LESS_OR_EQUAL is a recent error that affects Windows PCs. It is related to Wireless Keyboards and other USB-connected accessories accompanied by BSoD. Though the error can be annoying, we will outline a few fixes.

Also, you can checkhow to fix USB device not recognizedin Windows 11.

What causes DRIVER_IRQL_NOT_LESS_OR_EQUAL kbdclass.sys?

The following are some of the factors that may be responsible for the DRIVER_IRQL_NOT_LESS_OR_EQUAL kbdclass.sys error:

Though these factors vary on different computers, you can fix them by following the steps below.

How can I fix the BSoD DRIVER IRQL NOT LESS OR EQUAL kbdclass.sys error?

Before proceeding with any advanced troubleshooting steps, go through the following:

If you can’t resolve the error, try the steps below:

1. Reset the Driver’s changes

Rolling back driver changes will reset it to the version where it works correctly, removing faulty settings or updates.

2. Run an SFC scan

An SFC scan will find and repair corrupt system files causing the kbdclass.sys error. You can checkhow to fix the run as administrator option if it’s not workingon your PC.

Otherwise, you can opt for another effective method to repair OS files, so we advise you to try anautomatic repair tool.

The tool will check your Windows system for corrupted files and replace them with clean versions from its extensive repository.

3. Uninstall USB Controllers

Uninstalling the USB Controllers will allow your system to run and use new ones.

4. Update driver using Windows update

Updating drivers will improve the device’s performance and fix the kbdclass.sys. You can read aboutways to diagnose and fix Windows Update not loadingon your computer.

5. Run System Restore

Running System Restore will backdate the system and undo some recent system modifications on the PC. Read our guide onhow to fix Restore Point if it’s not workingon your PC.

Alternatively, you can learn about fixingthe Keyboard if it’s not working after Windows 10/11 rollbackon your PC.

If you have further questions or suggestions on this guide, kindly drop them in the comments section.

Fix: DRIVER_IRQL_NOT_LESS_OR_EQUAL (kbdclass.sys) BSoD#

What causes DRIVER_IRQL_NOT_LESS_OR_EQUAL kbdclass.sys?#

How can I fix the BSoD DRIVER IRQL NOT LESS OR EQUAL kbdclass.sys error?#

1. Reset the Driver’s changes#

2. Run an SFC scan#

3. Uninstall USB Controllers#

4. Update driver using Windows update#

5. Run System Restore#