How do I troubleshoot Windows 7 when it is stuck booting on classpnp.sys?

How do I troubleshoot Windows 7 when it is stuck booting on classpnp.sys? Since yesterday my main Windows 7 computer (an HP portable) won't boot. The apparent cause was a disk error, which seems to be fixed (but not sure, as chkdsk went fine. At first it couldn't find the boot loader (which I fixed with bootrec), and later complained of I/O errors in winload, later in other drivers.
Asked by: Guest \| Views: 554

Total answers/comments: 5

Comments display order:

bert [Entry]

"I would start by making a mirror copy or a full backup of the drive and then take a look at the SMART status of the ""failed"" drive.
Your best bet for a SMART utility should be to start at the Drive's manufacturer website and check what they offer as far as diagnose utilities.
Such utility may reveal that the drive is indeed failing or that the failure is at a logical level.
Based on that finding I would pursue either fixing the original drive (logical failure) or the mirrored drive (imminent drive failure).
Good Luck!"

bert [Entry]

"It looks like an imminent dead of your hard drive.

The first thing you should do it's a backup of your important data (with a bootcd or by plugging your hd in another computer)
After that you should do a true deep scan of your hd with the bootcd of your hard disk manufacturer.

And at this time, if you don't find no more error on the hard disk, you may think at saving your settings"

bert [Entry]

"Reinstall to another partition
Backup the data
Blank the hard drive
Run disk diags with ubcd
Move any bad sectors to the end of the drive partition
On your new installation leave 1GB unpartitioned
Think about purchasing a new hard drive"
"Reinstall to another partition
Backup the data
Blank the hard drive
Run disk diags with ubcd
Move any bad sectors to the end of the drive partition
On your new installation leave 1GB unpartitioned
Think about purchasing a new hard drive"

bert [Entry]

"I had only a few minutes a similar issue with Windows 7 RTM 64bit. Funnyly, I was then not able to boot any of my Windows OS on my system (at least the OS's I tried ;) Windows XP SP3 and the Windows 7 RC2 64bit).
The best is to check the BIOS (usually F2 on bootup) and switch some options off (in my case it was the USB legacy support). I also re-adjusted the USB devices, so, that Windows had ro look for them again. I guess, this distracts Windows so much, that it will boot properly and only then search for the correct drivers (Found new hardware and install drivers).
I had similar issues before. It must be something during the check for PNP hardware, where the Windows versions get stuck. This happens more and more with more advanced versions (i never had this with Win2k and lower and very rarely with XP, but Vista and Vista 64bit were worse). But currently this is quite regulary in Windows 7 64bit, even if I love its speed.
Best regards
T"

bert [Entry]

"Had the same problem. After hours of struggling, it has finally been fixed.
It was because of a conflict and incompatibility in the RAM modules. The modules aren't from the same company and have differences in timings. I had set the frequency to the highest available albeit the default was strangely lower.
After resetting the frequency to the defaults, Windows can be booted up again.

By the way this problem happened all of a sudden!"