Symptoms

  • Blue screen reading IRQL_NOT_LESS_OR_EQUAL, often naming a .sys file.
  • Crashes when connecting to Wi-Fi, waking from sleep, or launching a specific app.
  • Fresh crashes that began right after a driver or Windows update.

What causes IRQL_NOT_LESS_OR_EQUAL

  • A recently updated or mismatched device driver (network, GPU, audio, antivirus).
  • Faulty or unstable RAM, or an overclock that is not stable.
  • A corrupt system file or a filter driver from security software.

How to fix it

  1. Boot into Safe Mode and uninstall or roll back the most recently updated driver — start with network, GPU and antivirus drivers.
  2. Run Driver Verifier against non-Microsoft drivers (command below), reboot, and reproduce the crash to capture the faulting module in the minidump.
  3. Test RAM with mdsched or MemTest86, and if you overclock, return to stock speeds; update BIOS and chipset drivers.

Terminal / CLI command

verifier /standard /all

Elevated Command Prompt. If Verifier causes boot loops, start in Safe Mode and run: verifier /reset

How to confirm the fix: After removing the offending driver, the system runs normally for several days with no blue screen.

Prevent it from coming back

Install drivers from the device or PC maker rather than third-party updater tools, and keep only one security suite installed.