How to fix error 0x000000c9 in Windows 11

Solution Steps

1. 1 If you have Driver Verifier enabled, you need to disable it. Boot into Safe Mode: Press Windows key + I → System → Recovery → Advanced startup → Restart now. Then choose Troubleshoot → Advanced options → Startup Settings → Restart. Press 4 for Safe Mode. In Safe Mode, press Windows key + R, type 'verifier' and press Enter. Select 'Delete existing settings' and click Finish. Restart normally. This stops Driver Verifier from causing the blue screen.
2. 2 If you didn't enable Driver Verifier, it might have been enabled by a program or a Windows update. In Safe Mode, open Command Prompt as admin (right-click Start → Windows Terminal (Admin)). Type 'verifier /reset' and press Enter. This resets Driver Verifier settings to default.
3. 3 Identify the problematic driver. In Safe Mode, open Event Viewer (Win+R, type 'eventvwr'). Go to Windows Logs → System. Look for errors with source 'BugCheck' and note the driver mentioned in the event details. That driver is likely the culprit.
4. 4 Update the problematic driver. Open Device Manager (Win+X → Device Manager). Find the device related to the driver (e.g., network adapter, storage controller). Right-click and select Update driver → Search automatically. If no update, visit the manufacturer's website to download the latest driver.
5. 5 If you can't identify the driver, use Driver Verifier to pinpoint it. In Safe Mode, open Command Prompt as admin and type 'verifier /standard /all'. Restart. Windows will run Driver Verifier and the blue screen will show the faulty driver. Note the driver name, then boot back into Safe Mode and disable Driver Verifier as in step 1.
6. 6 After identifying the driver, uninstall it completely. In Device Manager, right-click the device and select Uninstall device. Check 'Delete the driver software for this device' if available. Restart and let Windows reinstall the default driver, or install the latest from the manufacturer.