Repeated BSOD irql_not_less_or_equal- Pfn list corrupt - ntkrnlmp.exe

Over the last week or so I've been having BSOD crashes at random intervals. Sometimes they seem to occur when my laptop has been asleep, or when it wakes up, but other times when I'm using it. When it crashes, I haven't been doing anything more strenuous than watching BBCV Iplayer on it. On some occasions it cites irq_not_less_or_equal as a problem, on others it cites pfn list corrupt and on yet other still it just says that it's collecting data and restarting and doesn't offer anything helpful.

I've tried removing the Nvidia Drivers and installing the latest version as suggested in a similar thread, but it hasn't stopped the crashes. Tonight I downloaded and ran "WhoCrashed" to see if I could glean anything useful, but other than pointing to ntkrnlmp.exe repeatedly and suggesting that I might have more luck with the pro version (no kidding!?), it didn't leave me any the wiser.

I've attached the report from WhoCrashed on the off chance that it's useful and I've attached the debug file hoping that someone that knows better what to look for will be able to offer advice.

Many thanks,

~Sandry

Hello Axe0, thanks for your quick response to my request help. I'm sad to report however that I've fallen at the first hurdle and things are now looking a lot worse.

Following your advice I went in search of the clwvd6.sys driver. If I understand correctly, it is a webcam driver that comes as part of an application called YouCam, which was bundled with my system. My system had YouCam 6. I found an update for the application which in turn updated the driver. I then discovered that there was a newer version still, YouCam 7, which I installed, going to find an even newer version of clwvd6.sys. More fool me. This installed a new driver, clwvd7.sys (you probably knew that already, right) and it's set off a while new problem.

Shortly after installing YouCam 7, my system crashed with a BSOD and kernel security check failure message. When the machine restarted, it showed a message about returning to a system restore point and two options: restore or cancel. I opted for restore. Since then it's been stuck in a loop where it says that it's preparing to restore, gets the kernel security check failure and reboots.

The machine is less than three months old and still under guarantee. Much as I'd like to pursue the issue with your help and enjoy the triumph of cracking the problem, I think it might be time to concede that discretion is the better part of valour, return the wretched thing to the shop and have them fix it under the warrantee. So unless you've got a really compelling reason not to go with this route, I'm planning to boot it up on a live CD, back up my data and code and return it to the store tomorrow.

Thanks again for your help :c)

Quick update on the situation:

I find the people that write insurance policies and guarantees to be more than a little slippery. So fearing that I might void my guarantee by attempting the reinstall myself, I took the machine into the shop. I explained and demonstrated the problem to the nice young man who referred it to his colleague. The KERNEL_SECURITY_CHECK_FAILURE (new BSOD error since original post) was dismissed with barely a wave of the hand as a software problem and therefore not covered under the guarantee. See what I mean? My options were to reinstall it myself or pay them fifty quid to do it for me. I took the machine home again.

Booting the machine was possible neither with the windows install media, nor with the F11 key (which I later discovered held system restore). After a bit more digging I found the built in information and diagnostics under the F3 key. It didn't take long after that to see it fail a quicktest on the RAM.

Back at the shop the following day a different young man did a passable impression of listening to my report of the problem before telling me that they shouldn't have sent me away without running some diagnostics. I told him about the tests on the RAM and he told me that a Hard Drive is like a little record player going round and round inside the machine with all the data on it and he then set about running some tests on the Hard Drive which it duly passed. I re-explained quietly and politely that it was the RAM that had failed the test, so we ran that test again and up came the same error code that I'd dutifully reported at the beginning of our conversation. All that remained to do after that was sign a couple of forms and my beautiful new laptop was whisked away to be returned to <wherever> for some intimate attention.

That was last Thursday, I doubt I'll see it again before this weekend. I'll let you know what happens next.

Thanks again for your help.

Well, my laptop came back from the workshop a few days ago. The technician's notes said, and I quote:

What we've found
The issue you reported was caused by a faulty memory and an outdated device driver.

What we've done
We have replaced the part listed below and updated some device drivers. To help prevent issues in the future we have also reinstalled your operating system and updated your BIOS. We then ran system checks to ensure your issue has been fully resolved.

What we've replaced
Memory

I bit my tongue and didn't ask if they reinstalled Windows after they "updated some device drivers" because although that's how it reads., I figured it was probably an unnecessarily facetious question.

The result is however that it's all working nicely now. My carefully installed applications is are all gone of course and my carefully removed bundleware is all back, but it's working properly and I'm a lot happier than I was a couple of weeks ago when it all kicked off.

Thanks again to Axe0 for jumping in to help so quickly.
Apologies to anyone reading this hoping to find a useful solution to a similar problem.

Hi Axe,

Sorry, I'm a bit dense tonight. Which log file should I upload? Is it the cbs.log?