How to Fix IRQL_NOT_LESS_OR_EQUAL in Windows 11

This guide walks you through fixing the IRQL_NOT_LESS_OR_EQUAL Blue Screen of Death (BSOD) in Windows 11. This error occurs when a driver or system process accesses memory at an incorrect interrupt request level, often due to faulty drivers, incompatible hardware, or corrupted system files. Follow the steps below to identify and resolve the underlying cause, restoring your PC to a stable state.

What You’ll Need

Administrator access to your Windows 11 PC
Your Windows 11 installation media (USB or DVD) or access to the Advanced Startup Options (in case Windows won’t boot normally)
A stable internet connection (for downloading drivers and running Windows Update)
Basic knowledge of your PC’s hardware (e.g., whether you recently added a new component)

Step-by-Step

Restart your PC. Sometimes a temporary glitch causes the error. If the BSOD appears only once and doesn’t recur, you may not need further action.
Boot into Safe Mode. If the error persists, restart your PC and press F8 (or Shift + Restart from the login screen) to access Advanced Startup Options. Navigate to Troubleshoot > Advanced options > Startup Settings > Restart, then press 4 or F4 to enter Safe Mode. Safe Mode loads only essential drivers, which can help isolate the problem.
Uninstall recently installed software or drivers. If the error started after installing new hardware or software, remove it. Go to Settings > Apps > Installed apps, find the suspect program, and uninstall it. For drivers, open Device Manager (right-click the Start button), right-click the device, and choose Uninstall device. Check the box that says Delete the driver software for this device if available.
Run Windows Memory Diagnostic. Faulty RAM is a common cause. Press Win + R, type mdsched.exe, and press Enter. Choose Restart now and check for problems. Windows will run a memory test and restart automatically. If errors are found, replace the faulty RAM stick.
Check disk for errors. Open Command Prompt as administrator (right-click Start > Terminal (Admin)). Type chkdsk /f /r and press Enter. If prompted, type Y to schedule the check on the next restart, then restart your PC. This scans for and repairs file system errors.
Update drivers. Outdated or incompatible drivers are the leading cause of IRQL_NOT_LESS_OR_EQUAL. Open Device Manager, expand each category, right-click devices, and select Update driver. Choose Search automatically for drivers. Pay special attention to network adapters, graphics cards, and chipset drivers. You can also visit the manufacturer’s website for the latest drivers.
Run Windows Update. Go to Settings > Windows Update and click Check for updates. Install all available updates, including optional ones, as they often include driver and stability fixes.
Use System Restore. If the error persists, restore your PC to a previous point when it worked. Search for Create a restore point in the Start menu, open the System Properties dialog, and click System Restore. Follow the wizard to choose a restore point and revert your system.
Run SFC and DISM. These tools repair corrupted system files. In Command Prompt (Admin), run sfc /scannow and wait for it to finish. Then run DISM /Online /Cleanup-Image /RestoreHealth. Restart your PC after both complete.
Check for overheating or hardware issues. Overheating can cause memory errors. Ensure your PC’s fans are working and vents are clear. If you recently added hardware, reseat it (remove and reinsert) to ensure proper connection.
Reset your PC. If nothing else works, you can reset Windows 11. Go to Settings > System > Recovery > Reset PC. Choose Keep my files to preserve personal data while reinstalling Windows, or Remove everything for a clean slate.

Common Mistakes

Skipping Safe Mode. Jumping straight to system restore or reset without isolating the issue in Safe Mode can waste time and may not fix the root cause.
Ignoring driver updates. Many users assume Windows Update covers all drivers, but some manufacturers (especially for graphics cards and network adapters) require manual updates from their websites.
Not checking RAM thoroughly. Running a quick memory test might miss intermittent errors. Use the extended test option (press F1 during the test) for a more thorough check.
Overlooking recent hardware changes. If you just installed a new SSD, RAM, or GPU, the error might be due to incompatibility or improper installation. Always reseat new hardware.
Using third-party driver updaters. These tools can install incorrect or malicious drivers. Stick to Device Manager or the manufacturer’s official website.

Tips

Note the error details. When the BSOD appears, take a photo or write down the stop code and any driver mentioned (e.g., rtwlanu.sys). This can pinpoint the exact culprit.
Create a system restore point before making major changes, so you can easily roll back if something goes wrong.
Use the Blue Screen View tool (from NirSoft) to analyze minidump files. It shows which driver caused the crash, saving you guesswork.
Keep your system clean. Regularly uninstall unused programs and avoid downloading from untrusted sources to reduce the risk of driver conflicts.
Update BIOS/UEFI. A outdated BIOS can cause hardware incompatibility. Check your motherboard manufacturer’s website for updates, but be cautious—a failed BIOS update can brick your PC.

Troubleshooting

If the error continues after following all steps, consider the following:

Check the minidump files. Navigate to C:\Windows\Minidump and open the .dmp files with a debugger like WinDbg. The analysis will reveal the faulting driver. If you’re not comfortable with debugging, use the Blue Screen View tool mentioned earlier.
Test hardware individually. If you have multiple RAM sticks, test them one at a time. Similarly, disconnect non-essential peripherals (printers, USB devices) to see if the error stops.
Check for BIOS/UEFI updates. Sometimes the error is due to a bug in the firmware. Visit your motherboard manufacturer’s support page and install the latest BIOS update.
Use System File Checker in Safe Mode. If SFC fails in normal mode, run it in Safe Mode to avoid interference from third-party drivers.
Consider a clean install. If all else fails, back up your data and perform a clean installation of Windows 11. This eliminates any software-related causes.

Frequently Asked Questions

What does IRQL_NOT_LESS_OR_EQUAL mean?

It’s a Windows stop code indicating that a driver or system process attempted to access memory at an interrupt request level (IRQL) that was too high for that operation. This is usually a driver or hardware issue.

Can this error be caused by overheating?

Yes, overheating can cause memory corruption, leading to this error. Ensure your PC has adequate cooling and that fans are working properly.

Will I lose my files if I reset my PC?

If you choose Keep my files during the reset, your personal files are preserved, but installed apps and settings are removed. Choose Remove everything only if you have backed up your data.

Why does the error happen only when playing games?

Games stress the GPU and memory heavily. A faulty graphics driver, overheating GPU, or unstable overclock can trigger the error under load. Update your GPU drivers and consider reverting any overclocks.

Is there a way to prevent this error in the future?

Keep Windows and all drivers updated, avoid installing suspicious software, and periodically check your PC’s health (memory, disk, temperatures). Creating regular restore points also helps.

Can a faulty power supply cause this error?

Yes, an unstable power supply can cause memory and driver errors. If you suspect your PSU, test with a known-good unit or consult a professional.

General steps for current mainstream versions; menus can differ by device and version. See the disclaimer or report an error.

More in this bed

The whole Tech How-To bed →