Get the fix for the error IRQL NOT LESS OR EQUAL on Windows 10, Windows 11, Windows XP, Windows Vista, Windows 7, and Windows 8.

About “IRQL NOT LESS OR EQUAL”

The following information on this error has been compiled by NeoSmart Technologies, based on the information gathered and reported by our global network of engineers, developers, and technicians or partner organizations.

Description and Symptoms

The error messages, alerts, warnings, and symptoms below are tied to this error.

Symptom 1: “IRQL NOT LESS OR EQUAL” blue error screen

The IRQL error is an extremely low-level error caused by a resource conflict between two or more devices connected to your PC. Because it involves the interaction between devices connected to your PC (internally or externally), your PC’s mainboard/motherboard, the Windows operating system, and the various devices drivers installed, it can be very difficult to track down and fix. You can read more about what an IRQL (Interrupt Request Level) is at Wikipedia.

The IRQL_NOT_LESS_OR_EQUAL error can be caused by any of the following, among others:

  • Faulty or incompatible PC components such as video card, onboard motherboard components, NVMe SSDs, USB controller, network card, and others
  • Faulty or incompatible external PC hardware such as mouse, keyboard, USB speakers, external drive, VGA/HDMI/network dongles, USB adapters, or similar
  • Corrupt system files
  • Incompatible device drivers
  • Incorrect software installation
  • An downgrade to a lower version of Windows, e.g. downgrading Windows 7 to Windows Vista

Here is an example of “IRQL NOT LESS OR EQUAL” error screen, first on Windows 11 then on Windows 7:

Your PC ran into a problem and needs to restart. We're just
collecting some error info, and then we'll restart for you.

25% complete

For more information about this and possible fixes, visit
http://windows.com/stopcode

If you call a support person, give them this info:
Stop code: IRQL_NOT_LESS_OR_EQUAL

And the following image depicts the IRQL_NOT_LESS_OR_EQUAL blue screen as it appears on Windows 7:

IRQL_NOT_LESS_OR_EQUAL error screen

A problem has been detected and Windows has been shut down to prevent damage 
to your computer.

IRQL_NOT_LESS_OR_EQUAL

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 make sure any new hardware or software is properly installed.
If this is a new installation, ask your hardware or software manufacturer
for any Windows updates you might need.

If problems continue, disable or remove any newly installed hardware 
or software. 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: 0x00000001 (0x00000001, 0x00000001, 0x00000000, 0x00000000)

Causes of this Error

This error has been known to occur as a result of one of the following causes:

Cause 1: Incompatible hardware device configuration

If you encounter this error on a brand new PC, after upgrading any of the hardware components in your computer, or when connecting an external device, this error is caused by a resource conflict between two or more internal or external devices connected to your computer.

Cause 2: Corrupt system files

If this error started “out of the blue” and did not happen after installing, connecting, replacing, or upgrading any PC hardware or components, then the most common cause for this error is a corrupted system file that is required to boot the system. This can happen because of virus attacks specially designed to cause IRQL_NOT_LESS_OR_EQUAL errors, power outages, or disk write errors during Windows system or manufacturer driver updates.

Cause 3: Incompatible device drivers

Another common cause is a newly installed or recently upgraded faulty device driver. In that case, reverting to an old version of a driver would be the best solution. If you can’t boot into Windows or Windows reboots with the blue screen too quickly for you to do this, then you will need to recover using EasyRE.

Cause 4: Faulty hardware items

This error can also be caused by a damaged motherboard, a bad RAM module, or failing internal/external hardware or components.

Cause 5: Incorrect software installation

Sometimes, this error may be caused by a misconfigured Windows service or registry error. This is typically the case if you run into this after installing a Windows update or after your PC says “applying updates,” or after manually installing an update to a driver.

Cause 6: A downgraded Windows installation

The least common cause for this error is when an older version of Windows is installed on top of a newer one. Sometimes, the system files are not replaced properly, and if that is the case, then the user should back up the files and perform a clean install to make sure there are no conflicts between different versions of Windows.

Fixing “IRQL NOT LESS OR EQUAL” on Windows

Fix #1: Disable memory cache

To disable the memory cache of your Windows system, you need to enter in your computer’s BIOS/UEFI menu.

Option 1

When your PC first boots, press Enter, Esc, Del, or F2 (depending on your PC’s make and model) to either boot directly into the BIOS or UEFI firmware setup subsystem or to display a menu that lets you press a key to boot into the BIOS or UEFI firmware setup. If you have a hard time getting this to work, refer to our guide on entering the BIOS depending on your PC or laptop’s manufacturer and model.

Option 2 (Windows 8, Windows 10, and Windows 11 only)

Follow these steps for Windows 8, Windows 10, and Windows 11 systems so you can open the UEFI menu:

  1. Start your Windows
  2. Press key and the C key to open the Charm Bar
  3. Click Settings
  4. Go to Change PC Settings
  5. Select General
  6. Click Advanced Startup
  7. Click Restart Now
  8. Go to Troubleshoot
  9. Select Advanced Options
  10. Click UEFI Firmware Settings
  11. Select Restart

Once you’ve entered the BIOS/UEFI menu of your system, follow these steps:

  1. Go to the Advanced Menu. Depending on your BIOS/UEFI version, this menu may have a different name.
  2. Find the Cache Memory option
  3. Hit Enter
  4. Select Disabled
  5. Press F10 to Save & Exit your changes
  6. Restart your computer

The option below may not be available on all PCs! If you don’t have this option, proceed to the next section or use EasyRE to attempt to automatically repair the IRQL_NOT_LESS_OR_EQUAL error.

Fix #2: Install latest updates

In some cases making sure your Windows has all the latest updates installed might fix the IRQL NOT LESS OR EQUAL error. Make sure your Automatic Updates option is turned on.

Follow these steps to check:

  1. Start Windows
  2. Windows Vista, 7 users can type update in the search box to open Windows Updates.
    Windows 8 users can open the Charm Bar by pressing key and the C keys and then go Settings > Change PC Settings
  3. Click Update and Recovery
  4. Click Choose how updates get installed
  5. Select Install updates automatically
  6. Check Give me recommended updates the same way I receive important updates check box under Recommended updates:

  7. Click OK

Under Windows 10, you will instead launch “Settings” by typing in “Settings” in the start menu and launching settings:

Then select “Windows Update” from the sidebar in the “Settings” app, and click on “Advanced Options”:

Then make sure you have “Pause updates” disabled and “Receive updates for other Microsoft products” enabled (to get device driver updates):

Windows should check for updates and let you know if there are any you can install.

Fix #3: Use EasyRE’s automatic repair and system restore options

If your IRQL_NOT_LESS_OR_EQUAL error is not resolved by the above steps or if there are no updates for your PC, you can use Easy Recovery Essentials for Windows to repair the IRQL_NOT_LESS_OR_EQUAL blue screen and other blue screens.

  1. Download a copy of Easy Recovery Essentials
  2. Insert a USB drive into any working PC and follow these instructions to create a bootable EasyRE USB.
  3. Insert the USB into the PC that needs repair and boot from the USB
  4. In EasyRE, select your Windows installation and initiate an automatic repair:
  5. Observe the repair log for any mention of blue screen fixes or corrected problems:
  6. After the automated repair has completed, use the Back button to go back to the main page, select your Windows installation again, and this time use the System Restore option and see if there are any restore points you can revert to.
  7. Reboot your PC to test if it worked.

Fix #4: Clean boot

If the IRQL NOT LESS OR EQUAL error is caused by a current running process, restart your Windows system using the clean boot method will allow you to troubleshoot if a current service or process is causing the error to appear.

With a clean boot only the necessary services and process that are required to operate Windows are started when you boot your computer.

Follow these steps:

  1. Start Windows
  2. Open Run. Windows 8 and Windows 10/11 users can press the key and R at the same time to open the Run dialog.
  3. Type msconfig and press Enter
  4. Go to General tab > check Selective Startup option and uncheck the Load startup items check box:
  5. Go to Services tab
  6. Check Hide all Microsoft services check box from the bottom left corner of the window, then click Disable all, and finally click OK:
  7. Restart Windows

To reset these changes and start your Windows normally, follow the same steps:

  1. Go to the General tab
  2. Check the Normal Startup option
  3. Click OK
  4. Restart

Fix #5: Remove unnecessary devices

A general fix for this error to remove all unnecessary hardware devices from your computer and test if it boots correctly. If it does, one of your hardware device might trigger the IRQL NOT LESS OR EQUAL error to appear.

Remove all the unnecessary hardware devices like peripherals, USB devices, and any other devices that your computer can run without.

More Information

Support Links

Applicable Systems

This Windows-related knowledgebase article applies to the following operating systems:

  • Windows XP (all editions)
  • Windows Vista (all editions)
  • Windows 7 (all editions)
  • Windows 8 (all editions)
  • Windows 8.1 (all editions)
  • Windows 10 (all editions)
  • Windows 11 (all editions)

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