Kbdclass.sys BSOD: How to Fix It on Windows 11

Is your Windows showing BSOD related to the kbdclass.sys? It’s most likely a driver-related stop-code error. If you want to know all possible ways to fix it, read this article.

Kbdclass.sys bsod while playing games like Volarant is a common issue many Windows users complain about. You may also face this issue after installing new hardware or software or because of corrupt drivers and outdated firmware. Some of the kbdclass.sys errors include-

• Kbdclass.sys was unable to load.
• Kbdclass.sys file is missing or corrupt.
• Windows was unable to start- kbdclass.sys.
• Kbdclass.sys could not be found

How to Fix Kbdclass.sys BSOD in Windows 11

DRIVER IRQL NOT LESS OR EQUAL kbdclass.sys error occurs while starting the PC or plugging in a keyboard device. Corrupt system files and USB Controllers issues also can be the root cause of this BSOD error. So, running a System scan, reinstalling the USB Controllers, and resetting the driver’s changes may resolve this problem.

Before applying other methods to fix it, try these quick methods first-

• Restart your System in Safe Mode and check if the error code appears.
• Temporarily disable Third-party Antivirus software.
• Scan for malware, and If any threats are detected, follow the recommended actions to remove them.

1. Uninstall/Reinstall USB Controllers

First, uninstall USB Controllers, then reinstall them. To do it-

1. Right-click on the Windows logo and select Device Manager.
   
2. Inside it, scroll down through the list of installed devices.
3. Select the Universal Serial BUS Controllers section.
4. Right-click on Generic USB HUB, then choose Uninstall device from the drop-down list.
   
5. Follow the same process for any USB Root Hubs entry.
6. Restart your PC, and the controllers will automatically be reinstalled.

Check if the  DRIVER IRQL_NOT LESS OR EQUAL (kbdclass.sys) BSOD error occurs.

2. Reset the Driver’s Changes

Reset the driver’s changes to fix the issue-

1. Press Win+R to open the Run dialog box.
2. Type the following command and click OK: hdwwiz.cpl
3. Right-click on the Keyboard Device, then head to Properties from the drop-down list.
4. Go to the Driver tab and click the Roll back driver option.
   
5. Restart your PC and check if the BSOD error occurs.

3. Run  SFC and DISM Scan

Use the following steps to run the System File Checker (SFC) and Deployment Imaging and Servicing Management (DISM) scan:

1. Right-click on the Windows logo and select Terminal (Admin).
   
2. In the Terminal window, type the following command and Enter: sfc /scannow
   
3. Wait for the scan to complete.
4. If the SFC scan detects any issues but cannot fix them, type the following command, Enter: DISM /Online /Cleanup-Image /RestoreHealth
   
5. This scan may take some time; restart your system after the DISM scan completes.

For more tips, learn how to repair system files properly.

4. Run System Restore

Performing a system restore to a previous point can help resolve kbdclass.sys  BSOD issue. Here’s how:

1. Open the dialog box like before.
2. Type the following command and click on OK: rstrui
3. You will see the System Restore Wizard, select Next, then put the date and time one after another when you start facing trouble shutting down.
   
4. Click on the Finish and select Yes to confirm the process.

Note: System Restore will undo any system changes made after the selected restore point, so back up any important files before proceeding.

To understand this process more clearly, learn how to use system restore properly.

5. Update Driver

Outdated or incompatible device drivers can create conflicts leading to DRIVER IRQL_NOT LESS OR EQUAL kbdclass.sys BSOD error. Update your drivers using the Device Manager with these steps:

1. Open Device Manager like before.
2. Expand the categories and look for devices with a yellow exclamation mark(!)
3. Right-click on the device and click on Update driver.
4. Select Search automatically for drivers.
   
5. Follow the on-screen instructions to install the updated drivers.

We suggest you use Driver Booster to update drivers on Windows 11 or 10. This dedicated tool is extremely powerful and can find and install the most stable drivers and solve various issues on your PC.

Extra Steps

If the above methods don’t work, try to follow these additional steps:

• Update Windows 11.
• Check for Hardware connections and clean the dust from your computer’s components.
• If none of the methods works for you, try seeking Professional Assistance.

---

We hope that we were able to give proper knowledge on how to fix kbdclass.sys BSOD error. You have to follow all the steps from the methods mentioned above correctly, and then the BSOD error won’t persist. If not, seek advice from a professional/expert.