DRIVER_IRQL_NOT_LESS_OR_EQUAL — Causes & Fix
Windows Stop code 0x000000D1 (DRIVER_IRQL_NOT_LESS_OR_EQUAL) means a driver tried to access pageable memory at an interrupt level that was too high — a specific driver is at fault (the dump names it).
- Applies to
- Any Windows PC
- Time to fix
- 30 minutes – 2 hours
What it means
Causes are almost always a buggy or outdated device driver — commonly network, wireless, or GPU drivers. This is a Windows Stop error (a "bugcheck" / blue screen) documented by Microsoft. The blue screen shows this code; more detail sits in the crash dump (%SystemRoot%\Minidump), which usually names the specific driver or component at fault — a free tool like BlueScreenView or WinDbg can read it.
Symptoms
- Blue screen citing DRIVER_IRQL_NOT_LESS_OR_EQUAL (often with a .sys file)
- Crashes when using a specific device (e.g. Wi‑Fi)
How to fix it
- 1
Update/roll back the named driver
1. Note the .sys file on the blue screen. 2. Update it, or roll it back if the crash started after an update.
- 2
Reinstall the device driver
1. Uninstall the device in Device Manager and reinstall the latest driver.
Frequently asked questions
0xD1 vs 0xA?
Both are IRQL faults. 0xD1 (DRIVER_...) specifically blames a driver and usually names the .sys file, making it easier to fix — update that driver.
Last updated July 20, 2026
Guidance only — always consult a qualified professional or the official service manual before carrying out repairs.