Acer Aspire E1-571 hangs on boot post-Windows update, appears to be corrupt driver

My daughter's Acer is 2.5 years old and it's running Windows 7. She recently rebooted it last week for a Windows Update and since then it starts up but hangs, with the hard drive light blinking slowly. I ran it in Safe Mode and it gets through CLASSPNP.SYS then hangs. According to articles this is usually a hardware problem. The only option I have with this OS is to bring up the Command Prompt. I've tried System File Checker - no go. System Repair comes back with unknown error and what looks like a bad Driver.

I was able to build a new partition (100+GB) and do a clean install of Windows 7 x64 Ultimate w/ SP1. This went through fine, though I would have to load the Acer drivers for the network card, etc. to finalize it. The point here is that this shows that the hard drive isn't the issue.

My fear is that Windows installed either some sort of driver or other update that has now caused the current OS on her laptop to be unusable. I went to do a System Restore and the only restore point it had was the Critical Update that she rebooted to on 2/13. Trying to roll back to that Restore Point didn't work.

Does anyone have any suggestions? Has anyone else experienced this post-Windows update apocalypse?

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IronFly

Boot to BIOS pressing F2, check if the SATA is set to IDE or AHCI, try to change it, save and exit BIOS.

try to boot.

WestSeattleCoug

Tried that early on. It was set to AHCI, setting it to IDE caused quick BSOD. I wish the BIOS has more options! BTW - I'm pretty conversant in computers - all of my desktop units are home-built and I'm a DBA. I even tried to rename CLASSPNP.SYS to .OLD to see if it would rebuild it (trying anything) and that didn't happen - not even the file rebuild/reload.

IronFly

i suggest you to create a bootable USB or CD media from Hiren's boot cd .iso
http://www.hirensbootcd.org/download/
unzip the zip file, burn the .iso file to CD or USB pen/external HDD, boot from your create media, then run some of the available utility to check HDD SMART atribute and check sectors.

WestSeattleCoug

I was looking at giving Hiren's a try - lots of good stuff out there. Because I've got a baseline W7 SP1 installed on a 2nd partition on the current HD, I was able to run Check Disk on the hard drive, but nothing was found. I'll let you know how it goes with Hiren's...unfortunately it will be tomorrow at the earliest.