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KMODE_EXCEPTION_NOT_HANDLED Blue Screen – Proven Fixes (2026)

Table of Contents

Hub: Windows 11 Troubleshooting Hub

Quick Answer
A KMODE_EXCEPTION_NOT_HANDLED blue screen typically indicates a faulty, incompatible, or corrupted device driver. The fastest fixes include disabling Fast Startup, updating or rolling back drivers, and running SFC and DISM to repair corrupted system files. If the error persists, checking your RAM for errors or performing a System Restore often resolves the problem.

Why KMODE_EXCEPTION_NOT_HANDLED Blue Screen Happens

When a KMODE_EXCEPTION_NOT_HANDLED blue screen appears, it means a kernel-mode program generated an exception that the error handler did not catch. This is a Windows Stop Error (bug check) that typically causes the system to crash and restart. The error code 0x1E is often associated with this BSOD.

Understanding why KMODE_EXCEPTION_NOT_HANDLED blue screen happens is the first step toward fixing it. The most common cause is faulty, incompatible, or corrupted device drivers. This can occur after a Windows update, a driver update, or a hardware-related change. The error may also be triggered by outdated network drivers, graphics drivers, or storage drivers. For a comprehensive overview of Windows errors, visit the official Microsoft documentation on this bug check.

Fast Startup is another frequent culprit. While Fast Startup helps your computer boot faster, it can preload problematic drivers, causing the KMODE exception to appear each time you start your PC. Disabling this feature resolves the issue for most users.

Other potential causes include corrupted system files, hardware problems such as faulty RAM or a failing hard drive, incompatible software, and recent Windows updates that introduced compatibility issues. For more Windows troubleshooting, visit our Windows 11 Troubleshooting Hub.

⚠️ Warning: If you see a file name in brackets at the end of the error message (e.g., ntoskrnl.exe, netio.sys), note it down—it will help you identify the problem driver.

1. Identify the Problem Driver

Before making any changes, check the KMODE_EXCEPTION_NOT_HANDLED blue screen message for any file name displayed in brackets. This will help you locate the problem driver later. Common culprits include:

  • ntoskrnl.exe – Windows kernel – may indicate system corruption
  • netio.sys – network driver – may indicate a network adapter issue
  • nvlddmkm.sys – NVIDIA graphics driver
  • clipp.sys – Windows system file – may indicate system corruption

If a file name is displayed, search for it online to identify the associated hardware or software. This will help you target the right driver for updates or removal.

💡 Quick Tip: If no file name is displayed, the issue may be related to Fast Startup or system corruption. Proceed to Method 3 (Disable Fast Startup).

2. Boot into Safe Mode

If the KMODE_EXCEPTION_NOT_HANDLED blue screen is preventing you from accessing your desktop, you will need to boot into Safe Mode to troubleshoot. Safe Mode loads only essential drivers, making it easier to identify and fix the problem.

  1. Interrupt the boot process three times: Start your PC. As soon as Windows attempts to load (spinning dots), press and hold the power button for 5–10 seconds to perform a hard shutdown. Repeat this twice.
  2. On the third startup, Windows will boot into the Recovery Environment.
  3. Select Troubleshoot > Advanced Options > Startup Settings > Restart.
  4. After the restart, press 5 or F5 to select Safe Mode with Networking.
  5. If you are unable to access the Recovery Environment, create a bootable Windows 11 USB on another working PC, boot from it, and select “Repair this Computer” to access the Recovery Environment.

✅ Expected Result: Your PC should boot into Safe Mode. If it does, proceed to the next methods. If Safe Mode also crashes, the issue is likely hardware-related.

3. Disable Fast Startup

Disabling Fast Startup is one of the most effective fixes for the KMODE_EXCEPTION_NOT_HANDLED blue screen. It resolves the issue for most users. Fast Startup preloads drivers, and if a problem driver is part of that preload, the error will recur each time you boot.

  1. Open the Control Panel (search for it in the Start menu).
  2. Click Power Options (or go to Hardware and Sound > Power Options).
  3. Click “Choose what the power buttons do” in the left-hand sidebar.
  4. Click “Change settings that are currently unavailable” at the top of the screen.
  5. Uncheck “Turn on fast startup (recommended)”.
  6. Click Save changes.
  7. Restart your PC and check if the error persists.

⚠️ Warning: If you use a traditional hard drive (HDD) instead of an SSD, disabling Fast Startup may cause your computer to boot more slowly. Only disable it if you are experiencing the BSOD.

4. Update or Roll Back Drivers

The KMODE_EXCEPTION_NOT_HANDLED blue screen is often caused by outdated, corrupted, or incompatible drivers. Updating or rolling back drivers is essential.

  1. Open Device Manager (right-click the Start button and select Device Manager).
  2. Look for any devices with a yellow warning icon (indicating a driver issue).
  3. Right-click each device and select “Update driver”.
  4. Select “Search automatically for drivers”.
  5. Roll back a driver: If the error started after a recent driver update, right-click the device, select Properties > Driver tab, and click “Roll Back Driver” (if enabled).
  6. Pay special attention to network drivers, graphics drivers, and storage drivers, as these are common culprits.
  7. If you identified a specific file name from the error message (e.g., netio.sys for network drivers), focus on that device.

🔁 Alternative Solution: Visit your PC manufacturer’s website to download and install the latest drivers directly, rather than relying on Windows Update.

5. Uninstall Recently Added Software

If the KMODE_EXCEPTION_NOT_HANDLED blue screen started after you installed new software, that program is likely the cause.

  1. Open Settings > Apps > Installed apps.
  2. Sort by Install date to find recently added programs.
  3. Identify any software installed right before the BSODs started.
  4. Click the three dots (•••) and select Uninstall.
  5. Restart your PC and check if the error persists.

❌ Common Mistake: Forgetting to restart after uninstalling. Always restart your PC to complete the removal process.

6. Run SFC and DISM

Corrupted system files can cause the KMODE_EXCEPTION_NOT_HANDLED blue screen. Running the System File Checker (SFC) and DISM tools can repair them.

  1. Open Command Prompt as Administrator (search for “cmd”, right-click, and select “Run as administrator”).
  2. Run the following command: sfc /scannow and press Enter.
  3. Wait for the scan to complete. If it finds and repairs corrupted files, restart your PC.
  4. If SFC doesn’t resolve the issue, run DISM /Online /Cleanup-Image /RestoreHealth.
  5. Wait for the DISM command to complete (this may take 15-20 minutes).
  6. Restart your PC and check if the error persists.

✅ Expected Result: SFC and DISM should repair any corrupted system files. If the KMODE_EXCEPTION_NOT_HANDLED blue screen persists, proceed to the next method.

7. Check RAM for Errors

Faulty RAM is a common cause of the KMODE_EXCEPTION_NOT_HANDLED blue screen. Use the Windows Memory Diagnostic tool to check your RAM for errors.

  1. Search for “Windows Memory Diagnostic” in the Start menu and open it.
  2. Select “Restart now and check for problems (recommended)”.
  3. Your PC will restart and begin the memory test. This process may take 20-30 minutes.
  4. After the test completes, Windows will restart automatically. The results will be displayed on the desktop or in the Event Viewer.
  5. If errors are found, you will need to replace the faulty RAM.

🔁 Alternative Solution: If Windows Memory Diagnostic doesn’t find errors but you still suspect RAM issues, try resetting your RAM by removing and reinserting the memory modules.

8. Use Driver Verifier

Driver Verifier is a powerful diagnostic tool that can identify problematic drivers causing the KMODE_EXCEPTION_NOT_HANDLED blue screen. Use it with caution.

  1. Open Command Prompt as Administrator.
  2. Type verifier and press Enter.
  3. Select “Create standard settings” (or “Create custom settings” for advanced users).
  4. Select “Automatically select all drivers installed on this computer” and click Finish.
  5. Restart your PC. Driver Verifier will stress-test drivers and crash the system (with a different error) if a problematic driver is found.
  6. Check the minidump file (C:\Windows\Minidump) to identify the driver that caused the crash.
  7. Important: After identifying the driver, disable Driver Verifier by opening Command Prompt as Administrator and running verifier /reset.

⚠️ Warning: Driver Verifier can cause your system to crash repeatedly. Only use it if other methods have failed, and remember to disable it after identifying the problematic driver.

9. Perform a System Restore

If the KMODE_EXCEPTION_NOT_HANDLED blue screen started after a system change, performing a System Restore can revert your system to a previous working state.

  1. Boot into the Recovery Environment (see Method 2).
  2. Select Troubleshoot > Advanced Options > System Restore.
  3. Choose a restore point from before the BSODs started.
  4. Follow the on-screen instructions to complete the restore.
  5. After the restore completes, your PC will restart.

💡 Quick Tip: If you don’t have a restore point, try uninstalling the latest Windows update from the Recovery Environment (Troubleshoot > Advanced Options > Uninstall Updates).

10. Repair Install with Windows Update

If none of the above methods resolve the KMODE_EXCEPTION_NOT_HANDLED blue screen, a repair install can fix system corruption without deleting your personal files.

  1. Open Settings > System > Recovery.
  2. Click “Repair with Windows Update” (if available).
  3. This option will keep your personal files while reinstalling Windows.
  4. Follow the on-screen instructions to complete the repair.
  5. If the option is not available, create a Windows 11 installation USB and run the repair from the installer.

✅ Expected Result: The repair install should resolve system corruption and eliminate the KMODE_EXCEPTION_NOT_HANDLED blue screen.

Advanced Troubleshooting for KMODE_EXCEPTION_NOT_HANDLED Blue Screen

If none of the standard methods resolve the KMODE_EXCEPTION_NOT_HANDLED blue screen, deeper system issues may be involved. Here are advanced solutions for persistent cases.

Disable C-States in BIOS:

  1. Some users have reported that disabling C-states (power saving modes) in the BIOS resolved the BSOD.
  2. Restart your PC and enter the BIOS/UEFI (usually by pressing F2, F12, or Delete during boot).
  3. Look for CPU power saving or C-states settings and disable them.
  4. Save changes and exit. Test if the error persists.

Check Disk for Errors:

  1. Open Command Prompt as Administrator.
  2. Run chkdsk /f /r and press Enter.
  3. Type Y to schedule the scan on the next restart.
  4. Restart your PC and let the scan complete. This will check for and repair disk errors.

Run Hardware Diagnostics:

  1. Most PC manufacturers provide built-in hardware diagnostics tools.
  2. Restart your PC and press the designated key for diagnostics (often F10, F12, or Esc during boot).
  3. Run a full system diagnostic, including RAM, hard drive, and CPU tests.

Clean Install Windows:

  1. If all else fails, a clean installation of Windows is the last resort.
  2. Back up your personal files to an external drive.
  3. Create a Windows 11 installation USB using the Media Creation Tool.
  4. Boot from the USB and perform a clean installation.

Contact PC Manufacturer Support:

  1. If the problem persists, contact your PC manufacturer for warranty support.
  2. They may provide additional diagnostics or hardware replacement.

For more Windows troubleshooting, explore our Windows 11 Troubleshooting Hub.

Conclusion

Encountering a KMODE_EXCEPTION_NOT_HANDLED blue screen is frustrating, but the vast majority of cases are resolved with the methods above. Start with the simplest fixes—disabling Fast Startup and updating drivers—before progressing to more advanced solutions like running SFC and DISM, checking your RAM, or performing a System Restore.

If you have tried every fix and the KMODE_EXCEPTION_NOT_HANDLED blue screen still persists, consider that the problem may be hardware-related. Run hardware diagnostics or contact your PC manufacturer for assistance. For broader Windows troubleshooting, explore our Windows 11 Troubleshooting Hub.

For similar BSOD and system crash issues, check out our guides on SYSTEM_SERVICE_EXCEPTION Fix or PAGE_FAULT_IN_NONPAGED_AREA Fix.

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FAQ

What causes a KMODE_EXCEPTION_NOT_HANDLED blue screen?

The KMODE_EXCEPTION_NOT_HANDLED blue screen is usually caused by faulty, incompatible, or corrupted device drivers, corrupted system files, Fast Startup issues, or hardware problems such as faulty RAM.

How do I fix KMODE_EXCEPTION_NOT_HANDLED on Windows 11?

Start by disabling Fast Startup in Control Panel > Power Options. Then update or roll back your drivers, run SFC and DISM to repair system files, and check your RAM for errors using Windows Memory Diagnostic.

Does disabling Fast Startup fix KMODE_EXCEPTION_NOT_HANDLED?

Yes, disabling Fast Startup resolves the KMODE_EXCEPTION_NOT_HANDLED error for most users. Fast Startup preloads drivers, and if a problem driver is part of that preload, the error recurs each boot.

How do I boot into Safe Mode with KMODE_EXCEPTION_NOT_HANDLED?

Interrupt the boot process three times: as soon as Windows attempts to load, press and hold the power button for 5–10 seconds. On the third startup, Windows will boot into the Recovery Environment. Select Troubleshoot > Advanced Options > Startup Settings > Restart, then press 5 for Safe Mode with Networking.

Can outdated drivers cause KMODE_EXCEPTION_NOT_HANDLED?

Yes, outdated, corrupted, or incompatible drivers are the most common cause of the KMODE_EXCEPTION_NOT_HANDLED blue screen. Updating or rolling back drivers often resolves the issue.

How do I identify which driver is causing KMODE_EXCEPTION_NOT_HANDLED?

Check the error message for a file name in brackets (e.g., ntoskrnl.exe, netio.sys). This file name indicates the problem driver. You can also use Driver Verifier to stress-test drivers and identify the culprit.

Is KMODE_EXCEPTION_NOT_HANDLED a hardware or software issue?

It can be either. The error is most commonly caused by faulty drivers or software, but it can also be triggered by hardware problems such as faulty RAM, a failing hard drive, or CPU issues.

Does resetting or reinstalling Windows fix KMODE_EXCEPTION_NOT_HANDLED?

Yes, a repair install (Settings > System > Recovery > Repair with Windows Update) can fix system corruption without deleting your files. If that fails, a clean installation of Windows is the last resort.

HowToFixPro Editorial Team

We’re a team of system administrators, technical writers, and platform specialists who genuinely enjoy solving the problems most users find frustrating. From persistent Windows errors and Android sync failures to browser crashes and network drops — we’ve seen it all, and we document every fix properly. Our guides are built on official documentation, direct testing, and real troubleshooting experience. No filler, no guesswork — just reliable, step-by-step solutions you can trust.

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