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Chip LevinsonFlag for United States of America

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Need Help Fixing W7 Desktop That Crashes on ClassPnP.sys.

This evening my wife's desktop made a funny noise (per her) and crashed. I think something went wrong with her HDD.  She said she was on the internet and some website had something pop-up that asked her to click somewhere and when she tried to close the window with the X in the upper right the screen completely froze. I do not know what the website was or what the popup said. I have tried several cycles of rebooting and the PC crashes shortly after Windows loads.  When I boot it Safe Mode the boot process hangs when it gets to ClassPnP.sys.  After a while it seemed to get past this roadblock but still crashed after Windws loads.

Her PC is an Acer Aspire X3950 running W7 Pro.  Almost a year ago I bought her a new PC with W10 Pro, but for a variety of reasons she never made the transition. I partially set up the new PC, but very much need to get some info/files off of her old sick one.  Some of the files I need include her Firefox Profile that has all of her Bookmarks and Passwords, her Outlook PST (although I may have recreated it), and some personal files.  I have a few ideas how to proceed, but if the HDD is really about to fail I want advice on the best way to proceed as I do not want to try trial and error.

In no particular order, my ideas include:
1. Get into BIOS and try changing SATA mode settings from IDE Engine to AHCI or visa versa
2. Figure out how to run chkdsk on the boot drive
3. Pull the boot drive out of the case and using a HDD dock try to connect it to my working W10 PC and see if I can get the needed files from it (as if it was an external HDD). Not sure how this would work since I would not be logged in as my wife and may not have permission to access to the folders where the files are stored.
4. Boot her sick PC into Linux and see if I can find and copy needed files to external flash drives
5. Using a SATA drive dock that supports to drives, mirror her drive contents to a blank HDD that I could either attempt to read or install in her case and try to boot.

Any suggestions on best course of action?

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Bios key is F2  - more :  How to Enter Setup on an Acer Aspire ( 
2. Figure out how to run chkdsk on the boot drive  - you can boot from a windows 7 usb stick and run chkdsk then

Follow these steps:
  1. Insert the original Windows disc.
  2. Restart your PC and boot from the disc.
  3. Click Repair your computer.
  4. Choose the operating system from the list.
  5. Click Next.
  6. Choose Command Prompt.
  7. When it opens, type the command: chkdsk C: /f /r.
  8. Press Enter.
3 you must grant access - and that can take some time

all other steps come into play when the above does not work
 to be complete see my article :
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thank you both for your comments. what if I cannot find the original windows 7 disk? is there a safe place to download an iso? I already removed hdd from case so when I get back home I may try Rindi idea first. I would like to repair had then upgrade to w10 to give desktop to my inlaws. Will keep you both posted.
You don't need the Windows 7 DVD. If you connect the HD to the other PC you should be able to access the data as long as the Disk or File-system aren't too damaged. Since you can boot at leat part way, I don't think there is too much to worry about in that respect. If you can't copy off the files because there is some File-System corruption, you can still open the Explorer, right click on the Old HD, "Property", "Tools", "Scan Drive", & allow it to fix errors it finds, that is the same as the chkdsk command nobus mentioned earlier. If there are corruptions which got fixed, it is pretty likely that you can then copy off your files. Possibly the OS will even start when in the original PC after that.

You can also download & run the HD manufacturer's diagnostic Utility to see if the Disk itself is the problem.
Hi rindi and nobus, a quick update.  So since I had the drive pulled from the case, I attached it to the new PC using a USB3 external drive dock. It popped up and a message said the drive needed to be repaired.  Under properties I selected check disk for errors.  The check disk took 1 second to run, said no problems and all the drives folders appeared in explorer. As expected I do not have access to the user account folders.  I am trying to grant Power Users access to her folder.  It is taking a long time and I have to skip a few files.  If this does not work, I may put the drive back in the old PC and try to boot it.  

Would it make sense to run the checkdisk on the drive while it is connected to a working PC in a drive dock?  Could I open up a CMD prompt as an admin, then type in "chkdsk F: /f /r" since th bad drive is Drive F not C? nobus I am going to read your article now.

UPDATE EDIT: After reading nobus' article I am going to skip the chkdsk option and instead have downloaded SeaTools for Windows and will run the complete diagnostics (after rebooting PC and checking that the bad drive is properly detected in BIOS).  I will update you when I have more info.
As I mentioned earlier, you should be able use file explorer right click the external disk, properties, tools, scan... It does the same as chkdsk does. But first I would suggest you rein the disk manufacturer's diagnostic utility on it. If it says the disk is bad, even chkdsk would probably not help too much.
rindi - thanks I have an update. Using SeaTools for Windows the drive passed the Short Drive Self Test, the Short Generic Test and provided drive information. It does not display a serial number and it FAILED the SMART test.  I did not start the LONG test as it will take hours.  When I looked up failed SMART test I read that it means that drive failure is imminent and data should be backed up. I have many extra HDDs lying around. And my main PC has two X-docks so I can attach the bad HDD and an empty HDD. Would it make sense to use robocopy and its mirror function to mirror the bad drive to a working drive of the same size?  If yes, is it K if the new empty drive is from Western Digital and not Seagate?

UPDATE - nobus, I should have read your article before starting my repair attempts! You mention that it is best not to try to diagnose and repair SATA drives via USB docks unless absolutely necessary. Don't know why I did not think of it, but I put the problem drive in one of my work PC's SATA X-docks.  It immediately said the drive needs, repairs.  This time when I ran the error checking from Windows it took almost 2 minutes to complete - not 1 second.  I loaded SeaTools on my PC and now the drive's serial number shows up in the software and it passed the SMART test. Definitely a step in the right direction.
No. But run the full Test. If there are no major issues run the file.system Scan & allow it to fix everything. Then copy the Data you need off again.
if you want a windows 7 iso, you must get it from ACer  eRecovery Media | Acer 

thank you both for your help. I was able to copy the Firefox profile out of the roaming folder onto the new pc then created a new profile and linked it to the copied folder. all passwords and bookmarks seem to be there. nobus everything worked better once drive was connected using SATA xdock vs USB. I am going to grab a fe more files then run a full scan and repair on the drive using SeaTools.