Fix IRQL_NOT_LESS_OR_EQUAL Errors in Windows 11/10

Few things are more frustrating than a Windows PC that suddenly freezes, flashes a blue screen, and restarts with the message IRQL_NOT_LESS_OR_EQUAL. The error can strike while you are gaming, editing a document, installing software, or even just booting up. In the worst cases it traps your computer in a restart loop, so you cannot reach the desktop at all.

The good news is that this Blue Screen of Death (BSOD) is rarely a sign that your PC is beyond repair. In most cases, it is caused by something fixable: a faulty or outdated driver, a misbehaving piece of software, a failing memory module, or corrupted system files. The stop code usually appears as 0x0000000A, and sometimes Windows names a specific file, such as ntoskrnl.exe, tcpip.sys, ndis.sys, or nvlddmkm.sys, that was running when the crash happened. That file name is an important clue.

This guide explains what the error means, why it happens, and walks through eleven proven methods to fix it on both Windows 11 and Windows 10, starting with the simplest and moving toward the more advanced. Work through them in order, and restart your PC after each one to check whether the problem is gone.

What Does IRQL_NOT_LESS_OR_EQUAL Mean?

IRQL stands for Interrupt Request Level. Windows uses IRQLs to decide which tasks get priority on the processor. Low-priority tasks, like ordinary programs, run at a low level. High-priority tasks, like hardware interrupts and kernel operations, run at a higher level.

The error appears when a kernel-mode process or driver tries to access a memory address it is not allowed to use at its current IRQL. For example, a driver running at a high level might try to touch memory that has been paged out to disk. Windows cannot allow that, so it stops everything to protect your data and system integrity, and shows the blue screen.

Common causes include:

• Incompatible, corrupted, or outdated device drivers, the most frequent culprit
• Faulty or poorly seated RAM
• Corrupted system files or a damaged Windows installation
• Recently installed software or Windows updates that conflict with existing components
• Overly aggressive antivirus or VPN software that hooks into the network stack
• Overclocking or incorrect BIOS and XMP memory settings
• Failing hard drives or SSDs with bad sectors
• Malware infections that tamper with kernel-level components

Knowing these causes helps you decide where to start. If the crash began right after you installed a new driver or program, begin with Methods 3 and 4. If the crashes seem random, start with the memory and disk checks.

Before You Begin: Get Into a Usable Environment

If your PC crashes too often to work normally, boot into Safe Mode first. Safe Mode loads only the essential drivers and services, which makes it much easier to apply fixes.

1. Turn on your PC and, as soon as Windows begins loading, hold the power button to force a shutdown. Repeat this two or three times until you see Preparing Automatic Repair.
2. Select Advanced options > Troubleshoot > Advanced options > Startup Settings > Restart.
3. After the restart, press 4 or F4 for Safe Mode, or 5 or F5 for Safe Mode with Networking, which lets you download drivers.

If you can reach the desktop normally, you can skip this step. It is also a good idea to back up your important files to an external drive or cloud storage before attempting deeper repairs.

Methods to Fix IRQL_NOT_LESS_OR_EQUAL

Method 1: Disconnect Recently Added Hardware and Restart

New hardware or a misbehaving peripheral can trigger the error, especially if its driver is faulty. Shut down your PC, unplug all non-essential devices (external drives, USB hubs, printers, webcams, game controllers, extra monitors), and keep only the keyboard and mouse connected. Start the PC and use it normally for a while.

If the crashes stop, plug the devices back in one at a time until the error returns. The last device you connected is the culprit. Try a different USB port, update that device’s driver, or replace the device if it keeps causing problems.

Method 2: Install Pending Windows Updates

Microsoft frequently patches driver and kernel bugs through cumulative updates. If you have been postponing updates, a fix may already be waiting for you.

1. Press Windows + I to open Settings.
2. Go to Windows Update (Windows 11) or Update & Security > Windows Update (Windows 10).
3. Click Check for updates and install everything available, including optional driver updates under Advanced options > Optional updates.
4. Restart your PC.

Method 3: Update, Roll Back, or Reinstall Device Drivers

Because faulty drivers are the number one cause of this error, this method resolves the problem for most people. Focus first on the drivers named in the blue screen message, then on network adapters, graphics cards, and storage controllers.

To update a driver:

1. Right-click the Start button and choose Device Manager.
2. Expand the relevant category, such as Display adapters or Network adapters.
3. Right-click the device and select Update driver > Search automatically for drivers.

Windows Update does not always have the newest version, so it is often better to download drivers directly from the manufacturer’s website: NVIDIA, AMD, or Intel for graphics, and your motherboard or laptop maker for chipset, audio, and network drivers.

To roll back a driver: If the crashes started after a driver update, right-click the device in Device Manager, choose Properties > Driver tab > Roll Back Driver. This restores the previous version.

To reinstall a driver cleanly: Right-click the device, select Uninstall device (tick Attempt to remove the driver for this device if shown), restart, and let Windows reinstall it. For graphics drivers, a tool such as Display Driver Uninstaller (DDU) run in Safe Mode removes leftovers that a normal uninstall misses.

Pay special attention to any device with a yellow warning triangle in Device Manager, since it signals a driver problem.

Method 4: Uninstall Recently Installed Software or Updates

If the error began right after you installed a program or a Windows update, remove it.

To uninstall a program: Open Settings > Apps > Installed apps (Windows 11) or Apps & features (Windows 10), select the recent program, and click Uninstall. Software that installs low-level drivers, such as virtual machine tools, VPN clients, disk utilities, RGB lighting controllers, and anti-cheat systems, is a frequent cause.

To uninstall a Windows update: Go to Settings > Windows Update > Update history > Uninstall updates, select the most recent update, and remove it. If it fixes the problem, you can pause updates for a short time until Microsoft releases a corrected version.

Method 5: Test Your RAM With Windows Memory Diagnostic

Faulty memory is the second most common cause of this error. Windows includes a built-in test to check it.

1. Press Windows + R, type mdsched.exe, and press Enter.
2. Choose Restart now and check for problems.
3. Your PC restarts and runs the test, which can take 15 to 30 minutes or longer depending on how much RAM you have.
4. After Windows loads again, the results appear in a notification. If you do not see them, open Event Viewer > Windows Logs > System and look for entries from MemoryDiagnostics-Results.

If errors are reported, shut down the PC, unplug it, and reseat each memory stick firmly. If you have more than one stick, test them one at a time in the same slot to identify the bad module, then try each slot as well. A faulty stick should be replaced. For a deeper test, the free tool MemTest86 runs from a USB drive and is more thorough than the built-in utility.

Method 6: Repair System Files With SFC and DISM

Corrupted system files can cause drivers and the kernel to misbehave. Two built-in tools can repair them.

1. Click Start, type cmd, right-click Command Prompt, and choose Run as administrator.
2. Run the System File Checker:
   sfc /scannow
   Wait for it to finish. It will report whether it found and repaired any problems.
3. Next, run the Deployment Image Servicing and Management tool, one command at a time:
   DISM /Online /Cleanup-Image /CheckHealth
DISM /Online /Cleanup-Image /ScanHealth
DISM /Online /Cleanup-Image /RestoreHealth
4. Restart your PC and, if DISM made repairs, run sfc /scannow once more.

DISM downloads healthy copies of damaged components from Windows Update, so make sure you are connected to the internet.

Method 7: Check Your Disk for Errors

A failing drive or damaged file system can also lead to this blue screen. Open Command Prompt as administrator and run:

chkdsk C: /f /r

You will be asked to schedule the scan for the next restart. Type Y, press Enter, and reboot. The scan may take a while on large drives. It fixes file system errors and flags bad sectors.

Also check the drive’s health with a tool like CrystalDiskInfo. If it reports a Caution or Bad status, back up your data immediately and plan to replace the drive.

Method 8: Temporarily Disable or Replace Third-Party Antivirus and VPN Software

Security suites and VPN clients install network filter drivers that sit deep in the system. Conflicts with these drivers commonly produce crashes that name files like tcpip.sys or ndis.sys.

Try temporarily uninstalling your third-party antivirus using the vendor’s official removal tool, then rely on Microsoft Defender, which is built into Windows and works well. Do the same with your VPN client. If the error disappears, either keep using Defender, or reinstall a newer version of your security software and check that it is fully compatible with your version of Windows.

While you are at it, run a full scan with Microsoft Defender (Windows Security > Virus & threat protection > Scan options > Full scan) or a trusted second-opinion scanner to rule out malware.

Method 9: Reset BIOS Settings and Remove Overclocking

Unstable memory timings, XMP or EXPO profiles, and CPU or GPU overclocks can all cause IRQL errors, even on healthy hardware.

1. Restart your PC and press the BIOS key (usually Delete, F2, or F10) during startup.
2. Look for an option such as Load Optimized Defaults or Load Setup Defaults and apply it.
3. Disable XMP or EXPO temporarily, and remove any overclock.
4. Save and exit.

If stability returns, you can re-enable XMP later and test again, perhaps with a slightly lower memory speed or higher voltage within the manufacturer’s specification. Also check your motherboard maker’s site for a BIOS update, since newer firmware often improves memory compatibility. Follow the update instructions carefully, as an interrupted BIOS flash can disable the board.

Method 10: Identify the Faulty Driver From the Crash Dump

If the error keeps returning, Windows has probably saved details about each crash. Reading them can point to the exact culprit.

1. Download a free tool such as BlueScreenView (NirSoft) or WinDbg Preview from the Microsoft Store.
2. Open the minidump files stored in C:\Windows\Minidump.
3. Look at the Caused By Driver column, or in WinDbg run !analyze -v.

If the same file appears repeatedly, search for what it belongs to. For example, nvlddmkm.sys is an NVIDIA graphics driver, rtwlane.sys is a Realtek wireless driver, and ntoskrnl.exe is the Windows kernel itself, which usually means the true cause is a driver or hardware fault that the kernel merely detected. Update or reinstall the related software, or remove the hardware responsible.

For even more aggressive testing, Driver Verifier (verifier.exe) stresses drivers to expose bad ones, but it can cause boot loops, so only use it if you are comfortable booting into Safe Mode to turn it off with verifier /reset.

Method 11: Use System Restore or Reset Windows

If nothing else has worked, roll back or refresh the system.

System Restore: Type rstrui in the Start menu or the Run box, and choose a restore point dated before the crashes began. This undoes recent system changes without touching personal files.

Reset this PC: Go to Settings > System > Recovery (Windows 11) or Settings > Update & Security > Recovery (Windows 10) and click Reset PC. Choose Keep my files to reinstall Windows while preserving your documents. Apps and settings will be removed, so be ready to reinstall them.

If the blue screen still appears after a clean Windows reinstall, the cause is almost certainly hardware, most likely RAM, the storage drive, or the motherboard. At that point, test components individually or take the machine to a repair technician.

Conclusion

The IRQL_NOT_LESS_OR_EQUAL error looks alarming, but it is one of the more solvable blue screens. In the large majority of cases, it comes down to a driver that is outdated, corrupted, or simply incompatible, which is why updating or rolling back drivers should be your first serious step. If that does not help, work through memory testing, system file repair, disk checks, and BIOS settings, and use crash dump analysis to narrow down the specific file responsible.

A few habits will help prevent the error from returning: keep Windows and your drivers up to date from trusted sources, avoid installing questionable low-level utilities, do not overclock without thorough stability testing, and create a restore point before major changes. Keep regular backups, too, so a crash never puts your files at risk.

With patience and a methodical approach, you can almost always get your PC running smoothly again without having to replace hardware.

Frequently Asked Questions (FAQ)

1. Is the IRQL_NOT_LESS_OR_EQUAL error dangerous for my computer?

The error itself is a protective measure, not damage. Windows stops running to prevent corruption when it detects an illegal memory access. However, repeated crashes can corrupt files or cause data loss if they happen while you are saving or installing something, and they may point to failing hardware such as RAM or a drive. Treat the error as a warning, back up your data, and fix the underlying cause rather than ignoring it.

2. Can faulty RAM really cause this blue screen?

Yes. Bad or poorly seated memory is one of the leading hardware causes. If a driver tries to read data from a damaged memory location, the system can raise this exact stop code. Running Windows Memory Diagnostic or MemTest86, reseating the modules, and testing each stick separately will quickly show whether RAM is to blame.

3. What should I do if the error keeps happening and I cannot boot into Windows?

Force your PC to shut down three times during startup to enter the Windows Recovery Environment. From there you can start Safe Mode, run Startup Repair, use System Restore, open the Command Prompt to run sfc /scannow and chkdsk, or uninstall the latest update. If you cannot reach recovery, create a Windows installation USB on another computer, boot from it, and choose Repair your computer.

4. Will reinstalling Windows definitely fix IRQL_NOT_LESS_OR_EQUAL?

Not always. A clean reinstall removes corrupted system files, bad drivers, and conflicting software, so it resolves software-related causes. But if the real problem is faulty hardware, such as defective memory, a failing SSD, or an unstable motherboard, the error will return after the reinstall. Test your hardware first, and use a reset or reinstall as a final step once you have ruled out the other causes.