How to Fix IRQL_NOT_LESS_OR_EQUAL (Windows Operating System)
Quick Answer
The IRQL_NOT_LESS_OR_EQUAL error indicates that a kernel-mode process attempted to access a memory address it did not have permission to access, often at an Interrupt Request Level (IRQL) that was too high. The fastest fix often involves updating device drivers or checking for corrupted system files.
What Causes This Error
- Outdated or corrupted device drivers, particularly for network adapters, graphics cards, or storage controllers.
- Corrupted system files or Windows installation.
- Hardware conflicts or faulty hardware components, such as RAM or a hard drive.
- Software conflicts, especially with recently installed programs or antivirus software.
- Incompatible or improperly configured BIOS/UEFI settings.
- Memory issues, including faulty RAM modules or incorrect memory timings.
Step-by-Step Fixes
1Update Device Drivers to Fix IRQL_NOT_LESS_OR_EQUAL
- Press the Windows key + X and select 'Device Manager' from the menu.
- Expand categories such as 'Display adapters', 'Network adapters', and 'Sound, video and game controllers'.
- Right-click on each device and select 'Update driver'.
- Choose 'Search automatically for updated driver software' and follow the on-screen prompts.
- Restart your computer after updating drivers to apply the changes.
2Run System File Checker (SFC) and DISM
- Press the Windows key + S, type 'cmd', right-click on 'Command Prompt', and select 'Run as administrator'.
- In the Command Prompt window, type 'sfc /scannow' and press Enter. Allow the scan to complete.
- After SFC completes, type 'DISM /Online /Cleanup-Image /RestoreHealth' and press Enter. Allow this process to complete.
- Restart your computer once both scans have finished to implement any repairs.
3Check for Windows Updates
- Press the Windows key + I to open Settings.
- Click on 'Update & Security' (or 'Windows Update' on Windows 11).
- Click 'Check for updates' and allow Windows to download and install any available updates.
- Restart your computer if prompted to complete the update installation.
4Disable Fast Startup
- Press the Windows key + S, type 'control panel', and open the Control Panel.
- Select 'Power Options', then click 'Choose what the power buttons do'.
- Click 'Change settings that are currently unavailable'.
- Uncheck the box next to 'Turn on fast startup (recommended)'.
- Click 'Save changes' and restart your computer.
Advanced Fixes
Perform a Windows Memory Diagnostic
- Save all open work and close applications.
- Press the Windows key + R, type 'mdsched.exe', and press Enter.
- Select 'Restart now and check for problems (recommended)'.
- Allow the tool to run during startup. This process may take several minutes.
- Windows will restart automatically and display the test results upon logging in.
Test RAM Modules Individually
- Power down your computer and unplug it from the power source.
- Open the computer case and locate the RAM modules.
- If you have multiple RAM sticks, remove all but one.
- Plug the computer back in and power it on. Use the computer as usual to see if the error recurs.
- Repeat the process, testing each RAM module individually in different slots if possible, to identify a faulty stick or slot.
Check Disk for Errors
- Press the Windows key + E to open File Explorer.
- Right-click on your C: drive (or the drive where Windows is installed) and select 'Properties'.
- Go to the 'Tools' tab and under 'Error checking', click 'Check'.
- Click 'Scan drive' if prompted. If errors are found, Windows will offer to repair them.
- Restart your computer if a repair requires it.
Frequently Asked Questions
What does IRQL_NOT_LESS_OR_EQUAL mean?
IRQL_NOT_LESS_OR_EQUAL is a Windows stop code (Blue Screen of Death) that indicates a kernel-mode process or driver attempted to access a memory address at an Interrupt Request Level (IRQL) that was too high, meaning it tried to access protected memory that it wasn't allowed to at that specific priority level. This often points to driver issues, corrupted system files, or faulty hardware.
Can faulty RAM cause IRQL_NOT_LESS_OR_EQUAL?
Yes, faulty RAM is a common cause of the IRQL_NOT_LESS_OR_EQUAL error. Memory corruption or incorrect memory timings can lead to processes attempting to write to or read from memory locations that are either invalid or protected, triggering this error. Running a memory diagnostic tool or testing RAM modules individually can help identify this issue.
Is IRQL_NOT_LESS_OR_EQUAL a hardware or software problem?
The IRQL_NOT_LESS_OR_EQUAL error can stem from both hardware and software issues. Software causes include outdated or corrupted drivers, system file corruption, or conflicts with recently installed programs. Hardware causes often involve faulty RAM, a failing hard drive, or other component malfunctions. Troubleshooting typically involves addressing software first, then investigating hardware.
Will reinstalling Windows fix IRQL_NOT_LESS_OR_EQUAL?
Reinstalling Windows is a comprehensive step that can resolve IRQL_NOT_LESS_OR_EQUAL if the root cause is software-related, such as deeply corrupted system files or irreconcilable driver conflicts. However, if the error is due to faulty hardware, reinstalling Windows will not fix the underlying problem, and the error will likely recur. It should be considered after other troubleshooting steps have been exhausted.
How do I prevent IRQL_NOT_LESS_OR_EQUAL from happening again?
To prevent the IRQL_NOT_LESS_OR_EQUAL error, regularly update your device drivers and Windows operating system, run routine system file checks, and ensure your hardware components are functioning correctly. Avoid installing unverified software and maintain good system hygiene. If you suspect hardware issues, replace or repair components as needed.