Fixes / Windows · Checked September 30, 2026

Windows KMODE_EXCEPTION_NOT_HANDLED: what it means and how to fix it

Short answer

KMODE_EXCEPTION_NOT_HANDLED (bug check 0x1E) means a driver running in the Windows kernel hit an error it could not handle, so Windows stopped to protect your data. The most likely fix is to find the driver named next to "What failed" on the crash screen, then roll it back or update it from the device maker's website. Start in Safe Mode if Windows keeps crashing.

What this message means

Windows runs drivers and core system components in "kernel mode", where a single mistake can corrupt the whole system. When one of those programs triggers an exception (for example, trying to read memory it should not) and nothing catches it, Windows halts with stop code 0x0000001E instead of risking data damage. Microsoft notes the cause is usually a faulty device driver or system service, with hardware problems such as bad RAM or BIOS incompatibility as the other main suspects. If a file name ending in .sys appears under "What failed", that driver is the prime suspect. On Windows 11 24H2 and later the crash screen may be black rather than blue, but the stop code means the same thing.

Common causes

Cause	How to tell
A faulty, outdated or newly installed device driver (network, Wi-Fi, graphics and audio drivers are the most common)	The crash screen shows a .sys file under "What failed" (for example a Wi-Fi or graphics driver), or crashes started right after installing a driver, device or Windows update.
A recent Windows update that conflicts with an existing driver	The crashes began the day an update installed, and Settings > Windows Update > Update history shows a quality or feature update from that date.
Fast Startup reloading a broken driver state on every boot	The crash happens soon after turning the PC on from shutdown, but a full Restart (not Shut down) boots cleanly.
Security software, anti-cheat or virtual drive tools that install kernel drivers	The named .sys file belongs to an antivirus, game anti-cheat, VPN or disk-mounting tool, or the crash happens when launching a specific game or app.
Faulty or badly seated RAM, or unstable overclock/XMP settings	The stop code changes between crashes (you also see MEMORY_MANAGEMENT or IRQL_NOT_LESS_OR_EQUAL), crashes are random, or Windows Memory Diagnostic reports errors.
Corrupted Windows system files	"What failed" shows ntoskrnl.exe or no file at all, and sfc /scannow reports that it found corrupt files.

How to fix it

1. Get into Windows (or Safe Mode) if it keeps crashing

If the PC restarts on its own and works, skip to the next fix. Microsoft notes a single crash is often resolved by the restart.
If it crashes in a loop, turn the PC on and hold the power button 5 to 10 seconds to force it off as soon as the Windows logo or spinning dots appear. Do this 3 times.
On the next start, Windows opens the recovery environment. Choose Troubleshoot > Advanced options > Startup Settings > Restart.
After the restart, press 4 (or F4) for Safe Mode, or 5 (F5) for Safe Mode with Networking if you need to download drivers.
Do the driver and update fixes below from Safe Mode, then restart normally.

2. Roll back, update or remove the driver named on the crash screen

Note the .sys file shown under "What failed". If you missed it, open Event Viewer > Windows Logs > System and look for an event with ID 1001 (BugCheck) around the crash time.
Search the file name online to find which device or program it belongs to (for example a Wi-Fi, graphics or antivirus driver).
Right-click Start, choose Device Manager, expand the matching category, right-click the device and choose Properties.
On the Driver tab, click Roll Back Driver if the crash started after a driver update. Otherwise click Update driver, or download the latest driver directly from the PC, motherboard or chip maker (Intel, AMD, NVIDIA, Realtek).
If the file belongs to antivirus, anti-cheat, VPN or disk-mounting software, uninstall that program from Settings > Apps > Installed apps (Windows 11) or Settings > Apps > Apps & features (Windows 10), then restart.
While in Device Manager, check for any device with a yellow exclamation mark and fix or update its driver too.

3. Uninstall the latest Windows update

Windows 10 and Windows 11 (menu paths differ, see steps)

Windows 11: open Settings > Windows Update > Update history > Uninstall updates.
Windows 10: open Settings > Update & Security > Windows Update > View update history > Uninstall updates.
Uninstall the update installed on the day the crashes started, then restart.
If Windows will not boot, use the recovery environment instead: Troubleshoot > Advanced options > Uninstall Updates > Uninstall latest quality update (or feature update).
Once stable, reinstall updates after checking your drivers are current, since the update often exposes an old driver rather than being broken itself.

4. Turn off Fast Startup

Open Control Panel > Hardware and Sound > Power Options.
Click Choose what the power buttons do.
Click Change settings that are currently unavailable.
Uncheck Turn on fast startup (recommended) and click Save changes.
Shut down fully and turn the PC back on to see if the crash returns.

5. Repair Windows system files

Right-click Start and choose Terminal (Admin) on Windows 11, or Windows PowerShell (Admin) / Command Prompt (Admin) on Windows 10.
Run: DISM /Online /Cleanup-Image /RestoreHealth and wait for it to reach 100%.
Then run: sfc /scannow
Restart the PC when both finish, even if they report nothing was fixed.

6. Test RAM and remove overclocks

If you enabled XMP/EXPO or overclocked the CPU or memory, set BIOS/UEFI back to defaults and test for a day.
Search Start for Windows Memory Diagnostic and choose Restart now and check for problems (recommended).
After it finishes and Windows starts, check Event Viewer > Windows Logs > System for the MemoryDiagnostics-Results entry.
On a desktop, power off, unplug, and reseat each RAM stick firmly. If errors persist, test one stick at a time to find the bad one.
Update the BIOS/UEFI from the PC or motherboard maker's support page, since Microsoft lists BIOS incompatibility as a known cause of 0x1E.

Next time, skip the search

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Still not fixed?

If the crash continues, try System Restore from the recovery environment (Troubleshoot > Advanced options > System Restore) to return to a point before the problem started. Run your PC maker's built-in hardware diagnostics (Dell SupportAssist, HP PC Hardware Diagnostics, Lenovo Diagnostics), especially the memory test. As a last resort, back up your files and use Settings > System > Recovery > Reset this PC (Windows 11) or Settings > Update & Security > Recovery (Windows 10). If crashes continue after a clean reset, the cause is almost certainly hardware: contact the PC maker or a repair shop and give them the minidump files from C:\Windows\Minidump.

Questions people ask

Is KMODE_EXCEPTION_NOT_HANDLED a hardware or software problem?

Usually software, specifically a driver. Faulty RAM, unstable overclocks and outdated BIOS are the main hardware causes, so test memory if updating drivers does not help.

What does it mean when "What failed" says ntoskrnl.exe?

ntoskrnl.exe is the Windows kernel itself, and it is rarely the real culprit. It usually means a driver or bad memory corrupted something the kernel was using, so follow the driver, RAM and system file fixes.

Can KMODE_EXCEPTION_NOT_HANDLED damage my PC or delete files?

The crash itself is Windows protecting your data and does not damage hardware. Unsaved work in open apps is lost, and repeated crashes during disk writes can occasionally corrupt files, so fix it promptly.

Why does it only happen after I shut down but not after Restart?

Fast Startup saves the kernel and driver state at shutdown and reloads it on boot, so a bad driver state is carried over. Restart does a full fresh load, which is why turning off Fast Startup often fixes this pattern.

What is stop code 0x0000001E?

0x0000001E is the numeric code for KMODE_EXCEPTION_NOT_HANDLED. Both names refer to the same crash.

Sources

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