BSOD on system boot, cant reach login. cng.sys

[wildozer]

Hi there,

So the other day I booted my computer up like normal and it got halfway through the four windows lights coming together to create the windows logo (after bios boot and just before user login screen) when it flashed with a quick blue screen then rebooted on its own accord. There's no way I can get past this point in the system boot that I've been able to figure out and I was hoping that someone here could help me.

I turned off automatic restart on system failure and it said something about the file cng.sys, so I am thinking that file has become corrupted somehow. Or am I way off. I don't recall installing anything new hardware or software-wise recently and I'm unsure how this happened.

Things I have tried:
Automatic startup repair
Removing CMOS battery and reinserting
Removing individual RAM sticks and trying each of the two separately
Unplugging everything from the back except the mouse and keyboard
Boot to safe mode
Flashing a BIOS Update
Inserting Windows 7 CD and doing a system restore and the other repair options on there
SFC scan with the Windows CD

I assembled the computer myself in 2010 sometime and it has
Gigabyte h67ma-ud2h-b3 motherboard
2x2GB RAM
GTX 560
Intel i5 2500
Corsair PSU - 500 watt I think?
card reader
optical drive

It seems I'm able to access the command prompt. Is there a way I can replace the cng.sys file with a good one or is that not something that would work? I am trying to avoid reinstalling windows as there is data that I would like to keep on the drive.

Any help is appreciated.
Thanks.

 

[wildozer]

I have since run a chkdsk, but still crashingbat the same point.
Can anyone help me please? I'm at a loss here

 

[Pauly]

cng.sys is a native windows file if there was a problem with sfc scan should repair it.
What were the results of your sfc scan ?

Have you checked your bios settings ? if you remove the cmos battery all settings will return to default so check everything is correct, there are some settings that if changed would leave your system unbootable for example changing sata mode from IDE to AHCI or vice versa and ram settings if they were manual before ie voltages/frequency

 

[wildozer]

Hi Pauly. So I just ran another SFC and this is a picture of the results.
Imgur: The most awesome images on the Internet
Still no startup

I don't know what BIOS settings to change, everything seems pretty much normal and in order. I never changed any voltages to begin with. I'll have another look.

How can I go about accessing that log file from command prompt?

At this stage it looks like I might need a new hard drive, reinstall windows and then recover my files off my current drive. But I'd rather not take that option if possible. Is my drive maybe failing?

 

[Pauly]

If you navigate to your system drive you will find the log at %root%/windows/logs/cbs/cbs.log which you can then copy to a flash drive from the command prompt. If you can upload that file we can get one of our SFC gurus to hopefully help you out. This may or may not be related to your boot issues.

While you are there navigate to the windows/minidump folder and see if you have any dump files for us to analyse this would help greatly in narrowing down your issue

 

[wildozer]

So I tried to copy to a USB in the command prompt but got an access denied error message.

I used this command here:
findstr /c:"[SR]" %windir%\Logs\CBS\CBS.log >"e:\sfcdetails.txt"

I just guessed e drive, but tried f and g also, but they gave a wrong file path error.

I altered from: findstr /c:"[SR]" %windir%\Logs\CBS\CBS.log >"%userprofile%\Desktop\sfcdetails.txt"

Since I obviously can't access the desktop.

I found the original command on this page. http://www.sevenforums.com/tutorials/1538-sfc-scannow-command-system-file-checker.html#option3

So basically I'm not sure how to access the log file since I can't access the desktop.

 

[NoelDP]

Please just post the CBS.log file (compressed)

You shouldn't have a problem copying the CBS.log file - use the following command

COPY C:\Windows\logs\cbs\cbs.log %userprofile%\desktop\cbs.log

That will put it on the desktop (OK - you can't see it at the moment!)

Now hunt for your USB stick - make sure that it contains a recognisable file in the root folder before you insert it on the machine (a Notepad file named TEST.TXT would be good)

run the following commands

DIR D:\TEST.TXT
DIR E:\TEST.TXT
DIR F:\TEST.TXT
DIR G:\TEST.TXT

Which one works?
Substitute the functional drive letter into the following command (for <drive>)

COPY %userprofile%\desktop\cbs.log <drive>:\CBS.LOG

It would be a good idea to also copy the Persist files, so use this command as well

COPY C:\Windows\Logs\CBS\CBSPersist*.* <drive>:\

Then you can close the machine down, and move the stick back to your functional machine and compress the copies for upload.

 

[wildozer]

Hi Noel.

So i finally got the log files with your guidance, thank you. Turns out i needed to be using D:\Windows... instead of C.

I've attached the compressed CBS.log but i'm going to have to give an external link to the persist files since as once all compressed, it added up to ~70mb. I have no idea if that's normal or not.

Persist files are here:
Mega File Upload - Log Files.rar

Will.

 

[Pauly]

That's great a good step forwards, we will have to wait and see what Noel says about the SFC results as I really don't know what I'm looking at but in the mean time did you try recovering the dump files from your machine ? would be good to have as look at these and may give us a better idea of whats causing the crash if its anything other than windows file corruption

 

[NoelDP]

Unfortunately the file doesn't contain any useful data
Please upload the C:\Windows\Logs\CBS\CbsPersist_20150821095015.cab file - you'll have to zip/rar it, since the forum doesn't accept bare cab files.

 

[wildozer]

Here is a link to the file you asked for, but it was just over the 8mb forum limit so I have to send you to an external download.
Mega File Upload - CbsPersist_20150821095015.zip

Will.

 

[NoelDP]

The only error there appears to be a transient one - Windows appears to have been attempting to conduct two installs at once, so the second got terminated.
The update involved is KB3080149

There's no SFC data there - and the log runs from 14/8 to 20/8, as expected.

Looking back at the CBS.log, three's no data in it after the 8th Sept?

Do you have any more recent files in the CBS folder?

 

[wildozer]

Hey Noel.

I posted all of the files in the cbs folder earlier at this link
Mega File Upload - Log Files.rar

I'm really just kind of fed up with all this though, it's been too long. What is the fastest way for me to recover my important files off the current harddrive? I'm willing to reinstall windows fresh and also to buy a new harddrive if need be. Am I able to reinstall windows without overwriting my data? I think it may have been installed on drive D (a partition on my single harddrive maybe? I really dont know too much).

Thanks,
Will.

 

[NoelDP]

Hi
You started this thread around a week ago - around the 23rd September.
There is no data in your CBS upload that is later than the 8th September.
What happened in the intervening two+ weeks?
It's that data I need

 

[wildozer]

::UPDATE FOR ANYONE WHO SEES THIS THREAD I FUTURE::
So I couldn't find any of the files you were looking for Noel but thanks for your help up until this point.

In the end I downloaded a USB bootable mini XP (it was part of Hiren's) and was able to boot up into that. From there I simply copied my important files off the hard drive in the computer onto an external USB hard drive.

After I had what I wanted I reinserted my Windows 7 CD and just did a new install. What happened next made me realise the whole USB OS thing was kind of pointless as well though. When I reinstalled windows, I didn't format my drive and just continued on with the install. The Windows installer was nice enough to recognise the old broken installation and put it all into a folder called Windows.old and then proceed with the fresh install.

So here I am on a fresh windows 7 install with access to my old files and folders in the Windows.old folder (as well as on the portable hard drive I made earlier). I wish I had have known it was this simple 3 weeks ago instead of dicking around trying to "Fix the BSOD" while having a useless tower in my room.

That's not to say I don't appreciate the help that was offered on this forum. Thankyou. But I think the above method(s) could save a lot of people some trouble in future as they are fairly straight forward.

Thanks again
Will

 

[NoelDP]

Glad you seem to have got yourself sorted!

Good luck.