Driver IRQL Not Less Or Equal: What, Causes, And How To Fix

driver irql not less or equal

IRQL_not_less_or_equal indicates that there may be a problem with your device’s memory, a device driver, or antivirus software.

By looking up the most recent Windows updates, confirm that your drivers are up to date. Select the Start button > Settings > Update & Security > Windows Update > Check for updates. Restart your device next. Select Start > Power > Restart.

Make sure your device is updated with the most recent versions.


NeoSmart Technologies has put together the information on this error below based on details gathered and reported by our international network of engineers, developers, and technicians or partner organizations.

Description and Symptoms

The following error-related error messages, alerts, warnings, and symptoms are related to this error.

“IRQL NOT LESS OR EQUAL” blue error screen

A resource conflict involving two or more connected devices to your PC can result in an extremely low-level error known as the IRQL. It can be very challenging to locate and fix because it involves the interaction of devices that are connected to your PC (internally or externally), your PC’s mainboard or motherboard, the Windows operating system, and the various device drivers installed. On Wikipedia, you can learn more about what an IRQL (Interrupt Request Level) is.

The IRQL_NOT_LESS_OR_EQUAL the 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 a mouse, keyboard, USB speakers, external drive, VGA/HDMI/network dongles, USB adapters, or similar
  • Corrupt system files
  • Incompatible device drivers
  • Incorrect software installation
  • A downgrade to a previous version of Windows, such as downgrading Windows 7 to Windows Vista

What’s Written in IRQL NOT LESS OR EQUAL Error?

The name of the offending program is often included in the “IRQL not less or equal” blue screen of death error. Some of these could be, but are not limited to, the following:

  1. kbdclass.sys
  2. ntoskrnl.exe
  3. usbxhci.sys
  4. ql2300.sys
  5. epfwwfp.sys
  6. e1c62x64.sys
  7. rdbss.sys
  8. rdyboost.sys
  9. rtkhdaud.sys
  10. rtwlane.sys
  11. tcpip.sys
  12. tap0901.sys
  13. tdx.sys
  14. usbport.sys
  15. usbhub.sys
  16. igdkmd64.sys
  17. netio.sys
driver irql not less or equal

After digging further, you can discover that most “IRQL not less or equal” BSOD files are related to broken drivers or equipment.

When a kernel-mode driver or Windows attempt to access pagefile memory at the incorrect process IRQL, an error will occur. In order to stop further damage, the computer will shut down in this case and display a blue screen and stop code.

When working with incompatible drivers or during computer startup, the IRQL not less or equal blue screen of death may appear. An antivirus program from a third party or CPU overclocking could be the cause of a driver failing to function.

This is primarily caused by a broken driver, another piece of software, or a device that has been configured incorrectly.


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

Incompatible Hardware Device Configuration

This error is brought on by a resource conflict between two or more internal or external devices connected to your computer if you experience it on a brand-new PC, after upgrading any of the hardware components in your computer, or when connecting an external device.

Incompatible Device Drivers

A faulty device driver that has just been upgraded or newly installed is another frequent cause. The best course of action in that situation would be to roll back to an older driver. You will need to recover using EasyRE if Windows won’t boot up for you or if it restarts too quickly for you to see the blue screen.

Corrupt System Files

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

Faulty Hardware Items

Additionally, a defective motherboard, faulty RAM, or failing internal or external hardware or components may be the source of this error.

Incorrect Software Installation

This error may occasionally be brought on by an incorrectly configured Windows service or registry issue. 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.

A Downgraded Windows Installation

An older version of Windows installed on top of a newer one is the least frequent reason for this error. To ensure that there are no conflicts between different versions of Windows, the user should back up the system files and perform a clean install when the system files are not replaced properly.

driver irql not less or equal

How to Fix “IRQL NOT LESS OR EQUAL” on Windows?

There are five methods listed for you to follow.

Method 1: Disable Memory Cache

You must access your computer’s BIOS/UEFI menu in order to disable the memory cache of your Windows system.

Option 1

When your PC first boots, press Enter, Esc, Del, or F2 (depending on your Depending on the PC’s make and model, the BIOS or UEFI firmware setup subsystem may start up automatically, or a menu may appear, from which you can select the BIOS or UEFI firmware setup by pressing a key. The manufacturer and model of your PC or laptop will determine which section of our guide to entering the BIOS to use if you are having trouble getting this to work.

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

On some PCs, the choice below might not be available. 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.

Method 2: Install the Latest Updates

In some cases, making sure your Windows has all the most recent updates installed may be able to resolve the IRQL NOT LESS OR EQUAL error. Make sure your Automatic Updates option is turned on.

driver irql not less or equal

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 a 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 to Give me recommended updates the same way I receive important updates check the 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 make sure you have “Pause updates” disabled and “Receive updates for other Microsoft products” enabled (to get device driver updates)
driver irql not less or equal

Method 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.

driver irql not less or equal
  1. Download a copy of Easy Recovery Essentials
  2. To create a bootable EasyRE USB, plug a USB drive into any functional PC and follow these steps.
  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 been 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. To see if it was successful, restart your computer.

Method 4: Clean Boot

If the IRQL NOT LESS OR EQUAL error is caused by a currently running process, restarting 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.

When you boot your computer with a clean boot, only the programs and services required to run Windows are launched.

driver irql not less or equal

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 the Services tab
  6. Check the 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

5: Remove Unnecessary Devices

A general fix for this error is to remove all unused hardware components from your computer and check to see if it boots properly. If it does, one of your hardware components could cause the IRQL NOT LESS OR EQUAL error to appear.

Remove any peripherals, USB devices, and other hardware that your computer can function without.

More Information

Support Links

  • The repair and recovery disk we use is called Easy Recovery Essentials for Windows.

    This automated diagnostics disk is simple to use. Windows 8, Windows 7, and Windows Vista are all supported. Additionally, it works with Windows Server and Windows XP.
  • The NeoSmart Support Forums, member-to-member technical assistance, and troubleshooting
  • Discounted setup and installation discs are available for Windows XP, Windows Vista, Windows 7, Windows 8, Windows 10, and Windows 11.

What Are the 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)

Conclusion About Irql Not Less Or Equal

This error suggests that your computer is unable to locate or identify the specific driver that is making use of an incorrect address. This error is usually caused by faulty, improperly configured, or corrupted drivers and it shows as a blue screen of death.