Learn how to fix the IRQL NOT LESS OR EQUAL error in Windows with these simple steps. Keep your computer running smoothly and efficiently.DRIVER IRQL NOT LESS OR EQUAL is one of the most common errors in Windows, usually appearing as a “blue screen of death”. What are the reasons for its appearance, and how to solve the problem? Let’s figure it out in this article.

What does the error DRIVER IRQL NOT LESS OR EQUAL mean?

The text of the message itself contains a hint, although only understandable to knowledgeable people and administrators. To find out the nature of the problem, it is necessary to decipher the code, dividing it into three components:

• DRIVER — the error affects the driver, possibly more than one. Most often, the problem lies here;
• IRQL — the system aborts the request or incorrectly handles priorities. The device incorrectly sets high priorities for different drivers or lowers them;
• NOT LESS OR EQUAL — «not less than or equal». This implies that the driver’s priority level has become equal to another one, the process of which it interrupts. It is worth knowing about the rule here — lower the level, higher the priority.

Causes of the error DRIVER IRQL NOT LESS OR EQUAL

The problem is complex. One process will not trigger this stop code, it is caused by a general hardware failure. To solve the problem ideally, it will be necessary to consider all possible options. 

Below are the most common and frequently encountered reasons:

• Incompatible drivers. Occurs after installing a new hardware device;
• Failed hardware. May mean damage to the motherboard or RAM;
• Virus impact. Most malicious applications cause complex damage to the system. It is quite possible that some Windows program files are damaged or missing altogether;
• Faulty registry. If the problem occurred after a software update, then the changes affected the registry;
• Partial driver installation. If the process is interrupted in the middle, the software will not function properly or even harm the system.

How to Fix IRQL NOT LESS OR EQUAL Error in Windows.

Since the problem is complex, several solutions will be required to completely repair the system. To do this, you need to consider the available options, choose the most suitable ones for your case, and even better, try everything one by one to return the system to working order.

Start Windows 10 in Safe Mode

Safe mode allows the system to function with a minimum number of functions and processes involved. If the cause is third-party software or a driver, this mode will prevent a repeat failure. To activate it, do the following:

• Go to Start, select Settings;
• Find the Update & Security icon;
• Find the “Recovery” section, click on “Restart now”;
• Next, select “Troubleshooting” — “Advanced options” — “Boot options” one by one;
• If the last block is missing, select “View other recovery options”, it is there;
• Click “Restart”;
• Next, a window will appear with different types of loading. To go to Safe Mode, you need to press the 4 key or F4.

Once completed, you need to reboot the device. If the problem disappears, then the cause was in third-party software.

Checking the disk for errors

The problem often occurs due to corrupted system files. To find out for sure, you need to check your hard drive, following the instructions below:

• Go to “Start”, enter “Command Prompt” in the search field;
• Right click and run it as administrator;
• There, enter the command chkdsk C:/f and press Enter. If necessary, replace the partition name with the corresponding letter.

Source: CQ / Checking a Disk for Errors Using the Command Line

Wait for the process to complete and restart your PC.

Checking memory and hardware

If the reason is not in the software, then the problem may be a hardware failure. To study the situation, you need to test the PC’s RAM. The system has a special tool for this case – Memory Diagnostic. To use it, do the following:

• Open “Start” and type “Memory Diagnostics” into the search bar;
• Open the utility, select “Restart now and check for problems”. The scanning process will start.

If the scan returns an error, then the source of the problem has been found. In such a situation, it is recommended to replace the RAM to restore functionality.

Update or restore

Sometimes the error pops up after making new settings. Here it is better not to test the strength of the system, but to roll back all changes or update the OS, if there is a new version. Rollback, also known as recovery, does not lead to the loss of personal files and data, but returns the computer to the state 12 or more hours ago. Updating the PC is easy – you need to go to “Start”, open “Settings”, find the “Updates and Security” section and check for them.

Source: CQ / Windows Update

If they are missing, then we proceed to recovery:

• Go to “Start” and find “System Restore” in the search bar;
• After going to the section, select “Create a restore point”;
• You will be taken to the next window. There you need to click on “System Protection” and “System Restore”;

Source: CQ / Windows Recovery

• Read the instructions on the screen and click “Next”;
• Check the box next to “Show more restore points”, select the time period before installing new settings. Click “Next”;
• Follow all the recommendations to the end and restore the system. Once completed, you need to reboot the device.

Launching hardware diagnostics

A hardware failure that caused the error may be the reason for the pop-up window with the notification DRIVER IRQL NOT LESS OR EQUAL. To make sure of this, you need to use another special system tool – hardware diagnostics.

It is done like this:

• Open “Start”, go to “Settings”;
• Click on “Update and Security”;
• There you will find the “Troubleshooting” section, select “Hardware and devices” in the column on the right;
• All that remains is to launch the tool and wait for the scan to complete.

Provided that the problem is hardware-related, the program will show it. If no defects are found, then you will have to look for the cause further.

Disabling memory caching

Windows 10 has a memory caching feature to store all data in the computer’s RAM. The advantage of this solution is the ability to quickly access important or lost information. At the same time, the option can even stop the error in question.

To do this, follow the instructions below:

• Reboot your device, press F1, F5, F8, Esc or Del during boot screen to open BIOS;
• Select additional settings from the menu;
• Press Enter to enter them;
• There, find two options – Shadowing and Cacheable RAM and press Enter on each. Set them to inactive – disable;
• When finished, exit the section by pressing the Esc key and press the Y key to save the changes.

Registry recovery

Before starting the process, it is recommended to create a backup copy of the registry. This will help to avoid fatal changes in case the system is significantly damaged.

Once ready, proceed as follows:

• Go to “Start”, search for “Command Prompt”, run it as administrator;
• In the window that opens, you need to write the command SFC/scannow and press Enter. Then the damaged files will be restored.
• Once completed, be sure to reboot your PC and check how the changes affected the system.

Reinstall Windows

If all previous solutions have been tried, and the DRIVER IRQL NOT LESS OR EQUAL error persists when starting the PC or appears as a notification, then one of the possible causes has not been found. There is only one option left – reinstall the system.

The measure is radical, but helps to solve the problem in the majority of cases. It is recommended to install a clean Windows, not a build, otherwise you can provoke new errors.

If the problem persists even after reinstalling the system, then the failure is mechanical in nature – one of the components is malfunctioning, but the OS considers its condition as “satisfactory” and does not report an error. There is only one thing left to do – contact a specialist to diagnose the components.