How-To

How to Fix Kmode Exception Not Handled on Windows 11

By Brian Burgess

Updated November 26, 2023

A blue screen of death can be tricky to fix on a Windows PC. If you’re seeing a Kmode Exception Not Handled BSOD on Windows 11, fix it with this guide.

Blue screen of death stopping your PC from loading? Don’t panic—you can usually fix the problem.

BSOD error messages, such as KMODE_EXCEPTION_NOT_HANDLED, are tricky to diagnose. This error is usually due to a corrupt driver or memory-related conflicts between apps.

Fixing the error is generally straightforward, but it might require additional troubleshooting steps depending on the system you have. To help you, here’s what you’ll need to do to fix a Kmode Exception Not Handled BSOD on Windows 11.

Disable Fast Start Up

The Fast Startup feature, introduced on Windows 8.1, is a hybrid power mode that combines Hibernation mode and shutdown properties. When you shut down your PC, it saves some of your PC’s system files to a hibernation file.

Windows uses the saved files in the Hibernation file created after enabling Fast Startup when you boot up your PC.

The Fast Startup option could cause the KMODE_EXCEPTION_NOT_HANDLED BSOD error. You can disable it by doing the following:

1. Click the Start button or hit the Windows key to open the Start menu.
2. Type CPL, scroll down the options on the right and click Power Options.
3. When Power Options in Control Panel launches, click the Choose what the power button does link in the left panel.
4. Now, click the Change settings that are currently unavailable link at the top.
5. Under the Shutdown settings section, uncheck the Turn on fast startup (Recommended) option, and click the Save changes button at the bottom.

With Fast Startup disabled, restart Windows 11 to see if you still see the error.

Clean Boot Windows 11

Another option to try is clean booting Windows 11. A clean boot will only use minimal drivers, services, and apps to load your PC. This can help you to determine if a driver issue or conflict is behind the BSOD message.

Note: This assumes that your Windows PC is still operational. If it isn’t, you may need to try and restart Windows in Safe Mode instead.

To clean boot Windows 11, use the following steps:

1. Open the Start menu and search for msconfig.
2. From the System Configuration window, click the Services tab.
3. Check the Hide all Microsoft services and click the Disable all button.
4. Next, click the Startup tab and click the Open Task Manager link.
5. When Task Manager opens, select the Startup tab and disable all startup apps.
6. Exit Task Manager, click Apply, and OK on the System Configuration window.
7. Now, it will prompt you to restart your PC – click the Restart button.

After the restart, the error should no longer appear. Note that you’ll want to go back and reenable one app or service at a time to find the item causing the issue.

Check Your RAM Integrity

If you’re still getting the Kmode Exception Not Handled BSOD on Windows 11, you may want to run a RAM diagnostic. Windows has a built-in utility called Windows Memory Diagnostic that you can run to check your RAM is working properly.

To run a diagnostic to check your system’s RAM, do the following:

1. Use the keyboard shortcut Windows key + R to launch the Run dialog.
2. Type MdSched and click OK or hit Enter.
3. Click the Restart now and check for problems (recommended) option when the Windows Memory Diagnostic tool opens.
4. The utility will scan your system’s memory for issues when your PC restarts.

Whether or not the Windows Memory Diagnostic utility finds errors, you can run a second scan using memtest86+, a free and open source RAM testing tool.

Update Your Network and Other Drivers

Another common reason for getting the error is outdated network drivers. Luckily, updating drivers is straightforward by doing the following:

1. Hit the keyboard shortcut Windows key + R.
2. Type devmgmt.msc and click OK.
3. When Device Manager opens, expand the Network adapters section, right-click the adapter, and select Update driver.
4. Follow the on-screen wizard and have Windows check for a new driver, or install an updated driver downloaded from the manufacturer’s site.

Also, scroll through other devices, and if you notice a red or yellow alert notification next to it, you’ll need to update that device’s driver, too.

Free Up Drive Space

If your drive is pushing the limits and is full, it can cause system issues, including the KMODE_EXCEPTION_NOT_HANDLED error.

You can easily clean up drive space on Windows 11 through Settings, and the Cleanup recommendations feature. Use the following steps to do this:

1. Click Start > Settings > System > Storage and scroll down to the Storage management section.
2. Select the Cleanup recommendations option.
3. Now, expand each section, including Temporary files, Large or unused files, Files synced to the cloud, and Unused apps. Decide which items to remove from each section and click the Clean up button.
4. It’s also worth noting that you can reclaim a more significant chunk of space from the Temporary files section – click See advanced options.
5. There you will find many more temp system files you can safely remove. You’ll also note a lot more space (10 GB in this example) can be reclaimed – click Remove files.

Check for Malware

Windows 11 includes the Windows Security app that scans for viruses and other malware in real-time. However, it might not catch everything, and stubborn malware could cause the error.

To scan your PC for malicious software, use the following steps:

1. Open the Start menu, type windows security, and click the top result.
2. Click Virus & threat protection on the left and click the Quick scan button on the right.
3. If the basic scan doesn’t detect anything, you can utilize a deeper system scan. Click the Scan options link, and select Full scan or Microsoft Defender Offline scan.

The deeper scans take longer but are worth it if deep-rooted malware is causing the BSOD. Whether or not Windows Security detects malicious code, try a virus scan with other free and trusted security suites such as Avast or AVG AntiVirus.

It’s also important to note that antivirus software could be causing the error by incorrectly quarantining essential system files. For example, if you’re using Microsoft’s built-in security suite, read how to disable or enable Windows Security in Windows 11.

If you are using a third-party security suite, read its support page for instructions on temporarily disabling it.

Fixing Kmode Exception Not Handled on Windows 11

While the above steps should resolve the BSOD error, you can also use other basic actions. For example, power down your computer altogether. Remove external peripherals, including external drives, mouse, keyboard, printer, or game controller, and power the PC back up.

If it works, plug in one device at a time and restart until you find the problematic device. You’ll then need to update the external device’s driver, replace a cord, or replace the device itself.

Also, it should go without saying, but make sure Windows 11 is up-to-date. Often, Windows updates include bug fixes and updated device drivers that resolve the error. Make sure to take a look at our guide on how to manually update Windows 11.

If none of the above fixes work, you’ll need to reset your PC. Before doing that, however, make sure to do a complete system backup so you can use the system image to restore the PC.

Windows 11 is much more stable than previous versions before it, but it’s not without problems. So, for instance, look at fixing Ntolkrnl.exe BSOD or fixing Windows 11 stop code memory management.