1. Introduction
I recently faced the IRQL_NOT_LESS_OR_EQUAL
blue screen error on my system right after a Windows update.
The system started crashing randomly
— sometimes during normal use, sometimes while opening apps. It became unusable
within minutes.
After testing multiple fixes
step-by-step, I was able to identify the cause and fix it completely.
In this guide, I’ll show you:
- What this error actually means
- Why it happens
- The exact steps that worked
🔍 What is IRQL_NOT_LESS_OR_EQUAL Error?
This error is related to how Windows
manages system memory and hardware communication.
IRQL (Interrupt Request Level) is used by Windows to assign priority to system processes.
👉 The error happens when:
- A driver tries to access memory it shouldn’t
- Or accesses memory at the wrong priority level
To prevent damage, Windows
immediately crashes the system (blue screen).
⚠When
Does This Error Occur?
You may encounter this error:
- After installing or updating drivers
- After a Windows update
- While gaming or heavy usage
- Due to faulty RAM.
How
to Approach This Error (Important)
Don’t try random fixes.
Follow this order:
- Update or rollback drivers
- Repair system files
- Check RAM
- Perform clean boot
👉 If none of these work → likely hardware issue
✅
Method 1: Update or Rollback Drivers
Faulty drivers are the #1 cause of
this error.
Steps:
- Press Windows + X → Device Manager
 |
| Device manager |
Expand categories like:
- Display adapters
- Network adapters
- Right-click the driver → Click Update driver
 |
| Display Driver |
👉 If the issue started after an update:
- Click Properties → Driver → Roll Back Driver
Why
this works:
Drivers control hardware. If they
send wrong memory requests → system crashes.
✅
Method 2: Run System File Checker (SFC)
Corrupted system files can trigger
memory-related errors.
Steps:
- Open Command Prompt as Administrator
- Run:
sfc
/scannow
 |
| SFC scan report |
- Wait for the scan to complete
What
this does:
It scans and repairs corrupted
Windows system files automatically.
✅
Method 3: Check RAM (Very Important)
If software fixes don’t work, RAM
might be the issue.
Basic
Check:
- Press Windows + R
- Type:
mdsched.exe
- Restart and scan
Advanced
Check:
- Turn off PC
- Remove RAM sticks
- Clean and reseat them
 |
| RAM stick |
 |
| RAM (Memory) slot |
👉 If you have multiple RAM sticks:
- Test one at a time
Why
this matters:
This error is directly linked to
memory — faulty RAM = frequent crashes.
✅
Method 4: Disable Overclocking / Reset BIOS
If you have enabled:
- XMP
- CPU overclock
👉 Reset BIOS to default settings.
Why
this works:
Unstable hardware settings can cause
invalid memory access.
✅
Method 5: Perform Clean Boot
This helps identify if third-party
software is causing the issue.
Steps:
- Press Windows + R → msconfig
- Go to Services tab
- Check Hide all Microsoft services
- Click Disable all
- Restart system
Result:
If the issue stops → some installed
software is causing the crash.
🔧 What Worked for Me (Real Case)
In my case, the issue started after
a Windows update.
After testing:
- SFC → no issues found
- RAM → no problem
👉 The actual cause was a network driver issue
Updating the driver completely fixed
the crashes.
⚠️
Common Mistakes to Avoid
- Ignoring driver updates
- Skipping RAM check
- Trying random fixes without order
📌 Final Thoughts
The IRQL_NOT_LESS_OR_EQUAL
error is usually caused by:
- Faulty drivers
- Corrupted system files
- RAM issues
👉 Best approach:
Start with drivers → then system → then hardware
🚀 Final Tip
If your system still crashes after
all fixes:
It’s most likely a hardware problem (RAM or motherboard).