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Windows 7: Crash with "DRIVER_IRQL_LESS_OR_EQUAL" & "iaStor.sys"

05 Dec 2010   #1

windows 7 64-bit
Crash with "DRIVER_IRQL_LESS_OR_EQUAL" & "iaStor.sys"


I purchased my SONY VAIO laptop over a year ago and it was working fine till today.

Today as I was watching a youtube video when my laptop crashed suddenly. No messages printed, it just powered off. Then when I rebooted it, I saw a blue screen message with some crash dump information. It specified "DRIVER_IRQL_LESS_OR_EQUAL" and other information I picked up from it was "iaStor.sys" was the file causing issue.. it contained some memory/register location such as 0x000xxxxxxxx..

So the next time when it rebooted automatically after the crash I ran it in safe mode and I was able to get there. Then after reading some forums and microsoft support I figured out it is better to disable certain devices as they may be causing problems. So i have disabled my network adapter and sound devices. But still whenever I reboot and run in normal mode my system crashes.

I also have the minidump messages stored in a pen drive. At present I can get my laptop working in safe mode. however If I shutdown then it restarts in normal mode and crashes. After reading some forums it looks like a hardware issue to me. However I'm not sure as it happened all of a sudden. Also this forum seems to point people most of the times in the right direction. Hence I thought it would be of great help to me if someone could point me in the right direction.

I appreciate your response. Please help me if you know anything about this crash.


My System SpecsSystem Spec
06 Dec 2010   #2

Systems 1 and 2: Windows 7 Enterprise x64, Win 8 Developer

My System SpecsSystem Spec
06 Dec 2010   #3

windows 7 64-bit

Thanks for the quick response Lemur. How can I get the BSOD Dump & System File Collection app (EXE file)?. I currently have the .dmp file which is not being accepted by SF.

My System SpecsSystem Spec

06 Dec 2010   #4

Systems 1 and 2: Windows 7 Enterprise x64, Win 8 Developer

You get the app by following the link above and clicking on the blue button (see attached button). When you finish following the instructions, the zipped file is attached via the paperclick found when creating a post on this forum.
My System SpecsSystem Spec
10 Dec 2010   #5

Windows XP Vista 7 x86 and x64 Mac OS X Leopard

I got same problem 2 days ago on Sony VAIO VPCF127FD.

I have a workaround for the issue.

What didn't work :
- Restore from restore point
- Install new or old drivers from Intel Matrix Storage Manager (tries 9.6 and 8.9)

What worked for me :
- Boot in Safe mode with command prompt (BSOD in regular Safe mode)
- Open device manager with command "devmgmt"
- Browse for "IDE ATA/ATAPI controllers"->"Intel...SATA AHCI Controller".
- Right-Click on it and select properties.
- In "Driver" tab, click on Roll Back Driver.

It will use driver version from digital signer "Microsoft Windows Driver Compatibility Publisher". Close all dialogs and reboot.

This worked for me since yesterday.
My System SpecsSystem Spec
22 Jan 2011   #6

Window 7 Home Premium 64
This solution worked for me

Posting this for others who are searching the BSOD/iastor.sys issue:

I had the same issues with BSOD/iastor.sys and couldn't boot most times. Spent a few days trying to rollback, repair, restore, even rebuild the MBR, but nothing worked. It turned out to be a nasty rootkit infection. Had to use kaspersky's tdsskiller.exe to kill it. I was able to boot into safemode with command prompt and run it (though 9 times out of ten safe mode would BSOD). Once I got it to run it took about 30 seconds to find it and kill it. See these threads and sites for more info:
BSOD, iastor.sys, windows 7 - Tech Support Guy Forums
How to remove malware belonging to the family Rootkit.Win32.TDSS (aka Tidserv, TDSServ, Alureon)?
Good luck!
My System SpecsSystem Spec
27 Jan 2011   #7

Windows 7
Thank you, thank you very much

heath3000, YOU ARE THE MAN !!

I spent two hard days starring at the BSOD with my HP dv6 until I thought I was back in WordPerfect 5.1 land!
As you suggested, I downloaded Kaspersky and readied it on my sandisk, practiced my movements and after the X-teenth reboot, I quickly installed and ran TDSSKILLER. Before the blue screen interrupted, the Rootkit was captured, the computer rebooted and returned to normal. All is good.

Thanks sevenforums and thanks, heath3000
My System SpecsSystem Spec

 Crash with "DRIVER_IRQL_LESS_OR_EQUAL" & "iaStor.sys"

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