Submit an edit

Get the fix to the <strong>0x0000007F: UNEXPECTED KERNEL MODE TRAP</strong> error message affecting <strong>Windows XP, Windows Vista, Windows 7, Windows 8, Windows 8.1</strong> and <strong>Windows 10</strong>.
<h2>About the "<strong>0x0000007F</strong>" error</h2>
[kbintro]
<h3>Description and Symptoms</h3>
The error messages, alerts, warnings, and symptoms below are tied to this error.
<h4>Symptom 1: 0x0000007F error screen</h4>
The error is usually triggered by two situations that occur in the kernel mode: either the CPU generated a condition that the kernel is not allowed to catch or the condition is an unrecoverable error.

<strong>The most common cause is hardware failure</strong>, mostly due to faulty or mismatched memory. There can be cases when faulty software currently installed on your computer can also make this error appear.

<a href="https://neosmart.net/wiki/wp-content/uploads/sites/5/2015/06/0x0000007F.jpg"><img class="alignnone wp-image-3477 size-full" src="https://neosmart.net/wiki/wp-content/uploads/sites/5/2015/06/0x0000007F.jpg" alt="0x0000007F error screen" width="980" height="490" /></a>
<pre>A problem has been detect and Windows has been shut down to prevent damage
to your computer.

If this is the first time you’ve seen this Stop error screen,
restart your computer. If this screen appears again, follow these steps:

Check to be sure you have adequate disk space. If a driver is
identified in the Stop message, disable the driver or check
with the manufacturer for driver updates. Try changing video
adapters.

Check with your hardware vendor for any BIOS updates. Disable
BIOS memory options such as caching or shadowing. If you need
to use Safe Mode to remove or disable components, restart your
computer, press F8 to select Advanced Startup options, and then
select Safe Mode.

Technical information:

*** STOP: 0x0000007F (0x0000000000, 0x0000000000)</pre>
On computers with Windows 8 the error code is replaced with <strong>UNEXPECTED _KERNEL_MODE_TRAP</strong>:

<a href="https://neosmart.net/wiki/wp-content/uploads/sites/5/2015/06/unexpected-kernel-mode-trap-windows-8.jpg"><img class="alignnone wp-image-3478 size-full" src="/wiki/wp-content/uploads/sites/5/2015/06/unexpected-kernel-mode-trap-windows-8.jpg" alt="UNEXPECTED KERNEL MODE TRAP error screen" width="980" height="490" /></a>
<pre>:(

Your PC ran into a problem and needs to restart. We’re just
collecting some error info, and then we’ll restart for you. (0%
complete)

If you’d like to know more, you can search online later for this error: UNEXPECTED KERNEL MODE TRAP</pre>
<h3>Causes of this Error</h3>
This error has been known to occur as a result of one or more of the following:
<h4>Cause 1: Faulty RAM module</h4>
The most common cause of this error is a faulty RAM module that periodically gives read/write errors. If that's the case, then it is advisable to scan the system memory and replace the faulty RAM module.
<h4>Cause 2: Corrupt or outdated device drivers</h4>
Sometimes the device drivers may become misconfigured, corrupt or outdated. That may also happen after a Windows update or a Windows downgrade from a newer system to an older one.
<h2>Fixing "0x0000007F" on Windows</h2>
<h3>Fix #1: Check new hardware</h3>
If the error occurs after a recent hardware installation, it's most likely that the error is caused by that specific hardware piece.

In order to fix the error, simply remove the new hardware and restart your computer.

If the error was caused after you've installed the driver of the new hardware, go to <a href="#Fix_3_Disable_faulty_drivers">Fix #3</a>.
<h3>Fix #2: Test RAM memory</h3>
The error can be triggered by faulty or mismatched memory.

If 0x0000007F occurs immediately after you've plugged-in a new RAM memory, shut down your computer, remove it and then restart your computer and check if the error was fixed.

If the error is caused by a faulty RAM memory, check your RAM using the <strong>Windows Memory Diagnostic Tool</strong>.

To do so, follow these steps:
<ol>
 	<li>Click <strong>Start</strong></li>
 	<li>Type in <code>Memory Diagnostics Tool</code> in the search box</li>
 	<li>Right-click on <strong>Memory Diagnostics Tool</strong></li>
 	<li>Choose <strong>Run as Administrator</strong></li>
 	<li>Follow the instructions to begin the diagnostic process</li>
</ol>
[caption id="attachment_4503" align="alignnone" width="980"]<a href="https://neosmart.net/blog/wp-content/uploads/sites/5/2015/06/Windows-memory-diagnostics.png"><img class="wp-image-4503 size-large" src="https://neosmart.net/blog/wp-content/uploads/sites/5/2015/06/Windows-memory-diagnostics-1024x592.png" alt="Windows memory diagnostics screen" width="980" height="567" /></a> Windows memory diagnostics screen[/caption]

If Windows Memory Diagnostic isn't returning any results, you can also use Easy Recovery Essentials' Automated Repair feature that can check your RAM, HDD and CPU in a single process:

[partial name="partial_easyre_hardware_testing"]
<h3>Fix #3: Update or disable drivers</h3>
To check if the error is caused by a faulty drive, run an automatic driver update or manually update the drivers to the latest available versions.

To manually update a driver, follow these steps:
<ol>
 	<li>Click <strong>Start</strong></li>
 	<li>Type in <code>devmgmt.msc</code> in the search box</li>
 	<li>Click <strong>devmgmt</strong> from results list</li>
 	<li>Right-click on the driver</li>
 	<li>To update the driver, select <strong>Update Driver Software</strong>.</li>
 	<li>To disable the driver, select <strong>Disable</strong>.</li>
 	<li>To uninstall the driver, select <strong>Uninstall</strong>.</li>
</ol>
[caption id="attachment_3363" align="alignnone" width="584"]<a href="https://neosmart.net/wiki/wp-content/uploads/sites/5/2015/04/device-manager-update-driver-software.jpg"><img class="wp-image-3363 size-full" src="/wiki/wp-content/uploads/sites/5/2015/04/device-manager-update-driver-software.jpg" alt="Device Manager screen" width="584" height="309" /></a> Device Manager screen[/caption]

To run an automatic driver update, follow these steps:
<ol>
 	<li>Click <strong>Start</strong></li>
 	<li>Go to <strong>Devices and Printers</strong></li>
 	<li>Right-click on your computer</li>
 	<li>Select <strong>Device Installation Settings</strong></li>
 	<li>Select <strong>Yes, do this automatically</strong></li>
 	<li>Click <strong>Save Changes</strong></li>
 	<li>Follow the necessary steps to continue the process</li>
</ol>
[caption id="attachment_4504" align="alignnone" width="980"]<a href="https://neosmart.net/blog/wp-content/uploads/sites/5/2015/06/Device_install.png"><img class="wp-image-4504 size-large" src="https://neosmart.net/blog/wp-content/uploads/sites/5/2015/06/Device_install-1024x592.png" alt="Device installation screen" width="980" height="567" /></a> Device installation screen[/caption]
<h3>Fix #4: Disable memory caching from BIOS</h3>
Follow these steps to open your BIOS menu and disable <strong>Cache Memory</strong> to test if the 0x0000007F appears afterwards:
<ol>
 	<li>Restart your computer</li>
 	<li>Press <kbd>F2</kbd> or <kbd>Del</kbd> key enter <strong>BIOS Setup</strong>

[caption id="attachment_1419" align="alignnone" width="450"]<a href="https://neosmart.net/wiki/wp-content/uploads/sites/5/2013/09/Dell-POST.jpg"><img class="wp-image-1419 size-full" src="https://neosmart.net/wiki/wp-content/uploads/sites/5/2013/09/Dell-POST.jpg" alt="Dell BIOS screen showing special key options" width="450" height="337" /></a> Notice the key guide in the top-right corner.[/caption]</li>
 	<li>Go to the <strong>Advanced</strong> menu</li>
 	<li>Select <strong>Cache Memory</strong></li>
 	<li>Make sure it's <strong>Disabled</strong></li>
 	<li>Press <kbd>F10</kbd> to <strong>Save &amp; Exit</strong></li>
 	<li>Choose Yes</li>
</ol>
<h2>More Information</h2>
[partial name="partial_moreinfo" versions="xp,vista,7,8,10"]