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Windows 7: Win7- slow boot, then black screen safe mode hangs on classpnp.sys

27 Sep 2017   #1

Win10 Pro x64
Win7- slow boot, then black screen safe mode hangs on classpnp.sys


I'm no stranger to troubleshooting necessarily, but as I'm worried this is a hardware issue, I come to ask for help. I'm a (very) long time lurker of this forum. Sorry for asking for your time to help me out!

We recently moved and his pc, the one that is now not functioning well, runs Windows 7 64bit. It's a custombuilt pc and has always worked like a charm, according to him. But because of the move, the pc may have dropped a bit, it thumped on the ground, so hence my reasoning this may actually just be a hardware issue, particularly because classpnp.sys problems seem related to hardware problems.

So in short - when you turn on the pc, the boot takes about 5 minutes. You get to the windows screen, it then turns in a black screen, then the desktop loads. It used to take 10 seconds, seeing as it's on a SSD.

So my reasoning was to do this -
1. Sort out updates. He never updates. 71 non-essential updates. This took extremely long, so I stopped to check out other venues first:
2. Check for malware. Nothing.
3. Check what's booting with ccleaner and what is currently running. Nothing weird or unnecessary, not even an antivirus.
4. Check system restore so I can maybe just go back in time and fix it this way. Mm, it doesn't load. AT ALL. Stuck on "preparing this may take some minutes".
5. PC in general seems a bit sluggish to my taste, but he assures me it is "working as always" once in Windows.
6. Go safemode to see if the slow boot happens there.

Aaand I CANNOT get into safe mode (w/o network). It hangs on classpnp.sys. Now I've read a couple of things 1) it's a bug in windows that you can hotfix. 2) from other forums, it seems also related to update problems, so should try system restore, but as I can't access that it's a bit rough, 3) it's related to hardware issues.

Now I've never accessed his safe mode before, so it could be that he always had a classpnp issue and we never knew.

I'm probably gonna end up doing a clean reinstall of Windows, but until then I'd like to see what you guys think. I'm going to go ahead and finish the unessential updates (and I will also reinstall his gpu drivers), I'm of a mind to try the hotfix because why not, and I'm gonna check his boot log just in case something else comes up.

Thanks for any input. Sorry for the long read.

My System SpecsSystem Spec
27 Sep 2017   #2

Win10 Pro x64

I've also tried to cmd -> chkdsk /f but it only returns it's a NTFS file format and then nothing happens. I haven't chckdisked in about 6 years, but this is not my memory of what chkdsk looks like. Any thoughts?
My System SpecsSystem Spec
27 Sep 2017   #3

W7 home premium 32bit/W7HP 64bit/w10 tp insider ring

Hi Charlieh,

have a look in device manager see if anything is
showing an !, a small down arrow or unknown device.

run KB947821, a repair tool

might also be handy if you run the tool from this tutorial, to provide more clues
Blue Screen of Death (BSOD) Posting Instructions - Windows 7 Help Forums

note it is NOT recommended to interupt windowsUpdates when in the configurations stages

My System SpecsSystem Spec

29 Sep 2017   #4

Win10 Pro x64

Thanks for your answer! I've had absolutely 0 time to look into this more since my post, but I'm eager to pick up where I left off. There are no BSODs, so not sure if that will be very handy.

I did not interrupt any windows updates while they were configuring, only the downloads, but maybe he has. He's very impatient when it comes to updates.

I'll check the repair tool. Pretty sure there were no unknown or weird devices in device manager, I already checked that, but can check again.
My System SpecsSystem Spec
29 Sep 2017   #5

Win10 Pro x64

Alright so there actually is a missing PCI driver. I can probably fix that (I say probably, because any install related to drivers or updates or anything that calls on system information is either super slow, or not working at all), but I think we're gonna have to go with a clean reinstall.

updates are NOT installing no matter what I do, I can't run the windows repair tool that you mentioned either, it's just not doing anything. There's an internet history worth 1000 pages on windows 7 and update problems, and at this point I'm beyond wanting to figure out exactly what the problem is without doing a clean reinstall.

I've also decided to upgrade that pc to windows 10, see if that helps
My System SpecsSystem Spec
29 Sep 2017   #6

W7 home premium 32bit/W7HP 64bit/w10 tp insider ring

Hi CharlieH

If its a pci card driver, thats your internet connection and would account for both problems youve just mentioned.

Id open it up make sure its seated correctly.
If not as its a custom build you should have the correct driver on your MB install disc, ethernet, or the card disc if its a plug in card

W7 comes driver complete, its possible you can internally install a driver
(in my w10 insider i have to reset my Asus wifi driver everytime)
Update driver >> computer >> let me choose >> UNTICK compatible device .. select manufacturer

My System SpecsSystem Spec
01 Oct 2017   #7

Win10 Pro x64

Yeah I'll open to check for seats, do you really think that PCI driver is also the reason why I can't use windows update, go into safe mode, and a lot of software seems slow to boot? Seems like a stretch. Internet is working just fine, just for the record.

I'll just download the drivers from his motherboard site. I'm not the one who built this pc, so I'm not sure if they ever bothered to install any chipset drivers.

It tried to update as I shut down the pc and it hung on "don't turn off this pc" for 11 hours before I turned it off. I didn't want to reinstall Windows before monday, in case it will refuse to install, a possibility I'm well-aware of, so he can still use his pc this weekend.
My System SpecsSystem Spec
01 Oct 2017   #8

Win10 Pro x64

Trying to install the drivers results in the expected: hangs endlessly at "preparing to install....."

It made it to install after a wait but has been stuck on 60% for past 15 minutes now and no signs of change.
My System SpecsSystem Spec
04 Oct 2017   #9

Win10 Pro x64

Tentative update ---

Whether or not this has anything to do with anything, I'm not sure. I proceeded to try and re-install windows from a bootable usb. I have two, one is for my pc, and it's a restore, and the other one is a complete windows. I accidentally used my restore usb and it booted just fine from usb, I was however very confused why it wouldn't install anything... DUH. So I put in the other bootable usb andddd... NADA.

Problem: Does not boot my USB. What I tried to fix:
- I went into his bios and wanted to alter the boot sequence. Not possible, USB device not listed. (USB WORKS 100%)
- I disabled Quick Boot as directed by google and checked again if it's listed. IT'S NOT LISTED.
- I literally do not know WTF at this point and boot Windows to check whats wrong with my USB. USB WORKS FINE.
- It runs checkdisk on the E: (not the windows drive) for the 100th time when it boots. IT STARTED CHCKDISKING BECAUSE I ABORTED A WINDOWS BOOT DURING THEE BOOT TODAY. THIS IS THE ONLY WAY I MANAGED TO MAKE IT CHCKDISK. It ALWAYS ends up returning the error that an unspecified error was encountered (usually means disk RIP, as far as I know). I was about to open the case and unplug E: disk, because at this point it's just in the way.
- IT COMPLETES THE CHKDISK WITHOUT ANY ERROR. Windows boots. I SEE MALWARE BYTES boots. This normally never boots as part of the problem. ITS FAST AS A RACING HORSE HOLY GOD. I can navigate folders without crashes. I CAN OPEN SYSTEM RESTORE. I CAN INSTALL UPDATES.

What fixed it? I did only two things: forced chkdisk, which was not doing anything, and disable fastboot. Problem that I can't boot from USB remains, but at least windows seems to be working, on this particular boot. I'm now instantly running a malware bytes scan and installing all windows update and going for a reboot later.

TL;DR is fastboot the culprit? can fastboot **** over chkdisk? or is the fact my chkdisk finally completed just random?
My System SpecsSystem Spec

 Win7- slow boot, then black screen safe mode hangs on classpnp.sys

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