- IRQL NOT LESS OR EQUAL errors is a BSoD that usually occurs when Windows is starting up. The cause for this is either an outdated or incompatible driver or a faulty software/hardware.
- What you need to do is isolate the cause: start by running memory diagnostics to rule them out, perform driver updates, check new software installed or disable memory caching in BIOS.
- If you have a Windows blue screen, check the error code to learn more. Use our BSoD Troubleshooting Hub to find out how to fix the problem.
- Visit our Windows 10 Errors Troubleshooting section for similar articles that touch many different areas and problems.
3. Refresh or Restore
Windows 10 offers users the possibility to refresh computers, which resets all the settings to their default values. This option will not affect any personal files you have on your computer, so you can run it without the fear of data loss.
However, if you’re facing a critical error and Windows deletes all your files in the update process, don’t panic just yet. We’ve written extensively about this and our guide will surely help you get all your files back.
A system restore is a viable options if the error manifested itself after you have installed multiple drivers and third party software. In order for this to work, you would need to have created a restore point prior to the install of the software.
This is a good habit to have, and creating restore points can prove a life saver. If you do have a restore point, you can revert back to that state, but all information added to the drive after the restore point was created, will be deleted.
Here’s how to run system restore on Windows 10:
If System Restore is enabled, follow the instructions listed below for Windows 10:
- Go to Search > type system properties > open System Properties.
- Go to System Protection > click on System Restore.
- Click Next > choose the preferred restore point in the new window.
- Once you’ve select your preferred restore point, click Next > click Finish.
- Your PC will restart and the restoring process will start.
Windows 10 offers a series of advanced recovery option that allows users to clean install the OS. If you’re a Windows 10 user, you can also use ‘Reset this PC’ recovery option.
- Go to Settings > Update & Security > click on Recovery under the left pane.
- Click on Get Started under Reset this PC > choose to Keep your files.
- Follow the on-screen instructions to complete the reset.
If you’re having trouble opening the Setting app, take a look at this article to solve the issue.
4. Repair your registry to fix corrupted files
As stated at the beginning of this guide, file corruption issues may also cause the irql_not_less_or_equal error. As a result, you can fix it by repairing your registry.
Note: Don’t forget to first backup your registry in case anything goes wrong so that you restore a working version of Windows.
The quickest way to do that is by using the System File Checker command in Command Prompt:
- Go to Start > type cmd > right-click Command Prompt > select Run as Administrator
- Now type the sfc /scannow command
- Wait for the scanning process to complete and then restart your computer. All corrupted files will be replaced on reboot.
If you prefer to repair your registry automatically, you can use one of these registry cleaners. Also, if you’re having trouble accessing Command Prompt as an admin, then you better take a closer look on this guide.
5. Check your disk for errors
Speaking of corrupted files and errors, your disk may also trigger the irql_not_less_or_equal error. If you already applied the first solution listed in this guide, and checked your RAM, try checking your disk as well.
On Windows 10, you can quickly run a disk check using Command Prompt.
Start Command Prompt as administrator and type the chkdsk C: /f command followed by Enter. Replace C with the letter of your hard drive partition.
As a quick reminder, if you do not use the /f parameter, chkdsk displays a message that the file needs to be fixed, but it does not fix any errors. The chkdsk D: /f command detects and repairs logical issues affecting your drive. To repair physical issues, run the /r parameter as well.
On Windows 7, 8.1 , go to hard drives > right-click the drive that you want to check > select Properties > Tool. Under the ‘Error checking’ section, click Check.
6. Run a full system scan
Malware may cause various issues on your computer, including the irql_not_less_or_equal BSOD error. Perform a full system scan in order to detect any malware running on your computer.
You can use Windows’ built-in antivirus, Windows Defender, or one of these third-party antivirus solutions.
Here’s how to run a full system scan on Windows 10:
- Go to Start > type ‘defender’ > double click Windows Defender to launch the tool
- In the left hand panel, select the shield icon
- In the new window, click the Scan options link
- Check the full scan option to launch a full system malware scan.
7. Perform a clean Windows install
If everything else fails, and the error still appears even after you have exhausted all alternatives, the only thing left to do is to perform a clean Windows install.
This means you will need a Windows installation disk or USB drive and you will delete everything on your C: drive and install a fresh version of Windows 10, but as mentioned, this should be left as a last resort.
If you want to know how to create a bootable USB drive with Windows 10 on it, check out this step-by-step guide.
The easiest and quickest way to do that is by using the Windows Refresh Tool. We’ve got a step-by-step guide on how to use the Windows Refresh Tool to clean install Windows.
Follow the steps listed in that article and let us know if that solution fixed the problem.
If you have any more questions, drop them in the comments section below.
Editor’s Note: This post was originally published in March 2014 and has been since completely revamped and updated in April 2020 for freshness, accuracy, and comprehensiveness.