Laptop hangs up at Classpnp.sys file.

Anonymous
2009-10-30T12:33:24+00:00

So I installed Windows 7 the other night on my laptop.  I did the driver updates and installed Norton.  I also installed Office 2007.  Then I shut it down for the night.  The next day I turned it back on to install a few more things.  A friend recommended that I install Ad-Aware, so I did, and ran it.  I've used it on a few of my machines before with no problems.  I installed a couple more programs (SANDRA & CPU-ID) then I shut it down for the night.  It stalled on shutdown.  I didn't think anything about it and after about 20 minutes I did the power-off.  I started it up the next day and it now hangs at the starting windows screen.  I've tried the following with all the same results:

  • System repair - hangs at the repair screen
  • Start normally - hangs at the starting windows screen
  • Start in safe mode - hangs at the classpnp.sys file
  • Start in safe mode with command prompt - hangs at the classpnp.sys file
  • start in safe mode with networking - hangs at the classpnp.sys file

I've even tried to put in the windows 7 disc back in to do a re-install and it hangs at the starting windows screen.

It seems like no matter what I try I get the hang up at the windows starting screen.

Someone help, please!!!

Windows for home | Previous Windows versions | Windows update

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Anonymous
2009-11-08T15:10:27+00:00

So the other night I tried a few more things with all the same results.  Here's what I tried:

  • I bought a second gig of ram, so I tried swopping out one stick, then the other - same results.
  • I bought a hard drive enclosure, removed the hard drive, formatted it with another computer, made sure I could save things to it, re-installed hard drive, booted from CD - same results.
  • I bought a brand new hard drive, installed it, booted from CD - same results.
  • Put old hard drive back in with both sticks of ram - same results.

After reviewing a few things, I found that when Windows gets to the "Starting Windows" screen, it's checking your hardware to make sure that things are OK.  Well, my hard drive, RAM, CD Drive, and Video Card are OK (I get all the right video stuff), so there's only a couple of things left, and one is the motherboard.  So, I believe that there is a hardware issue that is not allowing Win7 to completely load.

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Anonymous
2010-12-13T17:26:25+00:00

Go into your bios and check the hard drive configuration.   Once I reverted back to IDE the system booted as normal.  You may have to do the opposite!!!

At all times my system hung at classpnp.sys as advertised.  Let me know if this fixed

Macbionik.com

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  1. Anonymous
    2010-08-31T17:41:11+00:00

    Dena,

    I have the same prob. I clicked on the link you provided but I got this message: "You are not authorized to perform this action."

    Can you provide me with the solution to this prob?

    Thanks!

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  2. Anonymous
    2012-01-25T09:40:51+00:00

    Oki.. I believe the classpnp.sys confuses the issue.. It just so happens that it is the last driver to load which makes it look like it is the culprit. However I am not convinced. Our problem here has developped since we changed laptop model from Lenovo T410 to T420. Within the first month of use 90% of these freshly built machines would develop the hanging issue at startup. Because we use encryption, so far the only resolution I found to work is to mount the HD on a desktop with encryption installed thus allowing access to the HD. When starting up the desktop and after putting our encryption credentials, automatically W7 finds inconsistencies with the mounted drive and starts running a checkdisk. It seems to always find errors in Index files. Once checkdisk has fixed these errors I put the HD back in the laptop and  windows load without issues. 99% of the time we never see the problem again on the same machine. However, 1 laptop has now had this treatment 5 times so even if I have found a workaround. I am still trying to comprehend what causes it in the first place...

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  3. Anonymous
    2009-10-30T13:58:23+00:00

    I just tried to boot from the CD without the hard drive installed and it did the same thing - hang up at the starting windows screen.  Any suggestions?

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