How to fix boot loop that began with crash and stop code: KMODE_EXCEPTION_NOT_HANDLED (0x1E)

Question

How to fix boot loop that began with crash and stop code: KMODE_EXCEPTION_NOT_HANDLED (0x1E)

Morgan Owens 0

Hello,

I am using Windows 11 Home and trying to troubleshoot a boot problem that just occurred. I had just sent an email in Outlook when my screen froze for a minute before I got a blank black screen and the stop code KMODE_EXCEPTION_NOT_HANDLED (0x1E). The computer restarted into the Windows Recovery Environment, but none of the WinRE options have been helpful or successful (I get failure errors when I try to roll back recent updates or reinstall Windows). If I try to boot into Safe Mode, I get an "INACCESSIBLE_BOOT_DEVICE (0X7B)" stop code despite my UEFI BIOS being able to see my boot drive and the boot device (an M.2 drive seated on my motherboard) being physically installed. I am not able to boot into Windows 11 and am stuck in the WinRE or the motherboard UEFI BIOS.

The device this is happening on is a home desktop computer I built. I remember there being a Windows update installed yesterday, but I haven't updated any other drivers or made hardware changes recently. I'm writing this from an alternative device but would very much appreciate any troubleshooting or advice on how to get my main device back up and running.

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2 answers

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Answer 1

BryceSor 5,510 Volunteer Moderator

Hi Morgan Owens,

Can you list the make and model of your motherboard please?

Also make and model of the SSD?

In the bios does the motherboard see the SSD correctly?

Was it this update https://support.microsoft.com/en-gb/servicing/os/windows-11/2026/09/kb5129195-windows-11-24h2-25h2-security-update

Morgan Owens 0 Reputation points

2026-09-18T23:05:04.3833333+00:00

Hi,

Thanks for taking the time to respond.

The motherboard is an MSI x870 Gaming Plus Wifi and the SSD is a Samsung 4TB 990 Pro. In the BIOS, the motherboard can detect the SSD correctly and it's still first in the boot order.

It's hard to verify whether that's the recent update I can remember installing since I cannot boot into the main device now, but it looks like it was released around the right time for it to be the one that I most recently installed on my desktop, yes.
BryceSor 5,510 Reputation points Volunteer Moderator

2026-09-19T04:55:32.1+00:00

Can you get into WinRE at all? Use this method if you can't any other way
As soon as the Windows logo appears, hold the power button until it shuts off

Repeat this three times, the fourth time should give you WinRE.

then once in go to Troubleshoot, Advanced options, Startup Settings, Restart

Press F7 (Disable driver signature enforcement) or F9 (Disable automatic restart)

This stops the loop long enough to diagnose the failing driver

go to

Troubleshoot, Advanced options, Uninstall Updates

To repair the boot files go to

Troubleshoot, Advanced options, Command Prompt, do these one at a time (EDITED text to make it clearer)
bootrec /fixmbr

bootrec /fixboot

bootrec /rebuildbcd

Close Command Prompt, Restart

If it still doesn't get in to Windows go back to WinRE and use the following

Troubleshoot, Advanced options, Startup Repair

Just be aware if bit-locker is enabled as you might need the key which can be found in your MSA online.

https://support.microsoft.com/en-us/windows/security/encryption/find-your-bitlocker-recovery-key

Do you use Samsung software at all?
BryceSor 5,510 Reputation points Volunteer Moderator

2026-09-19T05:08:14.17+00:00

If you are un-sure of anything, please ask.

Answer 2

Since Safe Mode is also failing with INACCESSIBLE_BOOT_DEVICE (0x7B), focus on recovery paths that do not depend on a normal boot.

Remove any recently added hardware Even if no changes are expected, disconnect any nonessential USB devices and remove any recently added internal hardware before testing another boot.
Use WinRE or Windows installation media to reach recovery tools again If the built-in Recovery Environment is unreliable, boot from a Windows 11 USB and select Repair this computer to get back to the recovery options. This is the supported path when the normal recovery options are not resolving startup failures.
Try Safe Mode again from Advanced startup For stop code 0x1E, Windows guidance is to use: Troubleshoot > Advanced options > Startup Settings > Restart Then choose a Safe Mode option. If Safe Mode still immediately fails with INACCESSIBLE_BOOT_DEVICE, continue with offline repair steps below.
Check the system drive for file system errors from recovery Windows guidance for stop-code troubleshooting recommends checking the disk for file system errors. If the drive is visible in recovery tools, run the disk check from the drive’s properties path when available: Right-click drive > Properties > Tools > Check now
Run System File Checker for corrupted system files Stop-code guidance also recommends using System File Checker to repair missing or corrupted Windows system files:
```
   SFC /scannow
```
This is especially relevant because the crash started suddenly and WinRE rollback/reinstall attempts are failing.
Check Device Manager only if Safe Mode becomes available For KMODE_EXCEPTION_NOT_HANDLED, if a driver is involved, Windows guidance is to disable or remove the identified driver, or any drivers or services that were recently added. In Safe Mode, open Device Manager from the Start button menu and look for devices with an exclamation mark. Try Update driver first; if that does not help, disable or uninstall the affected device.
Check free space if the drive becomes accessible Windows recommends keeping roughly 10% to 15% free disk space available. Low free space can interfere with swap files and other system operations.
If startup is restored, install the latest Windows updates After recovery, go to Start > Settings > Windows Update and select Check for updates.
If recovery tools continue to fail, use System Restore or another recovery option If available, restore Windows 11 from a restore point or use one of the recovery options that best matches the scenario. This is the next supported step when the basic troubleshooting steps do not resolve repeated stop-code failures.
If files need to be protected before further recovery attempts From the Recovery Environment Command Prompt, launch:

notepad.exe

Then use File > Open as a basic file browser to copy personal files to a USB drive before attempting more invasive recovery steps.

What the stop code suggests:

KMODE_EXCEPTION_NOT_HANDLED (0x1E) is commonly associated with a faulty device driver or system service.
Hardware issues such as BIOS incompatibilities, memory conflicts, and IRQ conflicts can also cause it.
If the crash began after a Windows update and Safe Mode now throws INACCESSIBLE_BOOT_DEVICE, storage driver or file system corruption is a strong area to check first.

If the system still cannot boot after disk check, SFC, and restore attempts, the most supported next step is to boot from Windows installation media, enter Repair this computer, back up files, and continue recovery from there rather than repeatedly forcing normal boots.

References: