Windows 7 Forums
Welcome to Windows 7 Forums. Our forum is dedicated to helping you find support and solutions for any problems regarding your Windows 7 PC be it Dell, HP, Acer, Asus or a custom build. We also provide an extensive Windows 7 tutorial section that covers a wide range of tips and tricks.


Windows 7: OS not loading, Safe Mode won't boot past classpnp.sys

18 Jul 2014   #1
thebladeroden

Windows 7 64-bit SP1
 
 
OS not loading, Safe Mode won't boot past classpnp.sys

I replaced my Intel Q6600+DP35DP mobo with an i5-4690K and Asus Z97 K. I get a "missing operating system" message. When I boot up with a Windows 7 64 bit installation USB and then Repair Your Computer, it does find the OS on the hard drive still.

I tried following this guide for repairing the boot manager
How to Fix Windows 7 When It Fails to Boot

but I didn't get anywhere, until I tried this part
Quote:
*Some users also find simply deleting the boot folder and retrying the above steps effective at resolving boot issues, but it is not recommended.
Now instead of "Missing Operating System" I get the "Windows Error Recovery. Windows failed to start. A recent hardware or software change might be the cause" then it recommends I do the startup with the installation disc and repair my computer.

If I instead Start Windows Normally, it displays a few seconds of the startup animation then auto restarts.

If I chose Safe Mode, it shows Loading Windows Files until it gets to windows\system32\drivers\classpnp.sys, pauses for a second then restarts.

If I boot up with the installation USB again, and selecting my Windows installation it will tell me "You computer was unable to start; StartUp Repair is checking you system for problems" and start searching for problems for a few minutes, and then attempting repairs for a few minutes, and then it will give me "startup repair cannot repair this computer automatically"

And then it has these details.
Code:
Event Name: StartupRepairOffline
Signatures:
0.0.0.0
6.1.7600.16385
unknown
21200273
ExternalMedia
17
NoRootCause
OS Version: 6.1.7601.2.1.0.256.1
Locale ID: 1033
After that if I try to repair startup from the next screen it will give me "startup repair could not detect a problem" *shrug*

I've tried both SFC and DSKCHK but neither of them have reported any problems.


My System SpecsSystem Spec
.
18 Jul 2014   #2
matts6887

Windows 7 ultimate 64-bit
 
 

Well if im not mistaken; anytime you switch to a new motherboard; it is generally a good idea to do a completely fresh install of the windows operating system because the drivers for the motherboard will be different etc. But also; before doing a fresh install of windows; try following the steps in the following link and see if that doesnt help ya out. If not; post back and we can go from there.

Troubleshooting Windows 7 Failure to Boot
My System SpecsSystem Spec
18 Jul 2014   #3
bigmck

Windows 7 Home Premium 32-Bit - Build 7600 SP1
 
 

I agree with Matts6887 that a Clean Install Windows 7 is needed to get things going for you. You will need the Product Key to activate the Win 7 after it is installed. Since you have a Custom Build, I assume you have a Win 7 disk from your first installation. The Product Key will be on the DVD. == If your Win 7 DVD is a OEM copy, you are not allowed to use it again when a motherboard has been changed. OEM copies are tied to the motherboard and are not transferable. A new copy will have to be purchased.
My System SpecsSystem Spec
.

Reply

 OS not loading, Safe Mode won't boot past classpnp.sys




Thread Tools




Similar help and support threads
Thread Forum
Win7- slow boot, then black screen safe mode hangs on classpnp.sys
Hey, I'm no stranger to troubleshooting necessarily, but as I'm worried this is a hardware issue, I come to ask for help. I'm a (very) long time lurker of this forum. Sorry for asking for your time to help me out! We recently moved and his pc, the one that is now not functioning well, runs...
Performance & Maintenance
Newly installed 980, unable to boot (safe mode freezes at classpnp.sys
Just got a GTX 980 (Asus reference) and when I've got it installed it freezes at "Starting Windows" and I have to hold the power button it to restart it. When trying to boot to safe mode, the computer hangs on classpnp.sys I know it's not the graphics card as it boots on my friend's computer...
General Discussion
Cannot get past Loading Pge when turning on my PC, safe mode works.
Hey all, When I turn on my PC I can get to the ADMIN or my user, but after I enter the password I get the blue loading circle and then the PC freezes. I tried to run a system restore by pressing F8, but it says I do not have any restore points. I have run system restore previously with no...
General Discussion
BSOD on boot logo, safe mode stuck at classpnp.sys
Hi guys, I need help on my Acer 4750G here. I've been lurking around the internet lately searching for this problem's solution. But no answer :cry: Here's the story: So this morning my I started my laptop, it kinds of frozen/lagged so I had to shut it down via holding the power button 'till the...
BSOD Help and Support
PC Hangs on Boot And on Safe mode at CLASSPNP.SYS, Setup-fix not work
My signature Pc, the one I had problems last week is misbehaving again. It hangs while trying to Boot at the "glowing-pulsing colors" thingie. If i try to boot in Safe mode it Hangs at CLASSPNP.SYS If i boot from the Windows Setup DVD , or a repair DISK I've made, and i choose to do a...
BSOD Help and Support


Our Sites

Site Links

About Us

Find Us

Windows 7 Forums is an independent web site and has not been authorized, sponsored, or otherwise approved by Microsoft Corporation. "Windows 7" and related materials are trademarks of Microsoft Corp.

Designer Media Ltd

All times are GMT -5. The time now is 20:45.
Twitter Facebook Google+ Seven Forums iOS App Seven Forums Android App