Windows 7 freezes at «Starting Windows» but most often when computer is cool

New HD, installing Windows fresh after serial «Starting Windows» freezes and some dummies in another (cough, SevenForums, cough) forum saying «it must be your hard drive, even though you’ve tested the wazoo out of it with the proprietary tools from the manufacturer and it checks out okay.»

So: new hard drive! New install!

Freeze on «starting windows.»

Here’s the weird thing: NO FREEZE when I’m installing software. NONE. I stripped it down to Windows 7 SP1 with all updates after the last «Starting Windows» freeze in System Restore. Restart it FIVE TIMES. No problems!

Install my audio drivers. Restarted it from a cold boot EIGHT TIMES. Perfect! NOTHING IN THE EVENT VIEWER. NO PROBLEMS.

Go to work, come home, boot: FREEZE AT «STARTING WINDOWS!»

Strip it BACK DOWN to Windows 7 + SP1 only.

Another FIVE COLD BOOTS. PERFECT. NOTHING IN THE EVENT VIEWER. NO PROBLEMS AT ALL.

Go to work, come home, boot: FREEZE AT «STARTING WINDOWS!»

I’m at a loss. Is there some sort of hobgoblin that freezes my computer ONLY WHEN IT HAS BEEN POWERED DOWN FOR MORE THAN AN HOUR?

(I have over FORTY HOURS OF MEMCHECK 86+ RUN WITH NO ISSUES.

I HAVE TESTED THE HARD DRIVE WITH CHKDSK AND PROPRIETARY MANUFACTURER SOFTWARE.

HARDWARE IS ***NOT THE ISSUE***.)

Replies (2) 

Sorry however hardware is the issue.

Since you replaced the hard drive and re-installed Windows the issue has to be hardware,
BIOS, low level chipset drivers, and/or other drivers which load at a low level (such as the
video) — and hardware is the most likely cause. It is not that unusual for a problem to clear
when an electronic component is warm and show up when it is cold (though the opposite
is more often the case). An example would be an open in a circuit that closes when the
component warms up and expands or a short (less likely) that clears when the component
warms up and expands. Could be motherboard, video card if a separate device, or other
hardware.

When you replaced the hard drive did you use a new cable? Worth checking.

Check with a real computer shop (one that does its own in-house service and not leeks
and peeks at a Best Buy or other Big Box Stores) or the System Maker’s Support. Also
ask in their forums for any known issues.

Sorry this is not what you wanted to hear however this is not a Windows problem (it it was
there would be millions with the same issue).

Hope this helps and Happy Holidays!

Rob Brown — Microsoft MVP Rob Brown — past Microsoft MVP — Windows Insider MVP 2016 — 2021
Microsoft MVP Windows and Devices for IT 2009 — 2020

Windows 7: freezes at the ‘Starting Windows’ screen — Classpnp.sys

original title: Windows 7: startup freezes at the ‘Starting Windows’ screen. Maybe Classpnp.sys problem

my computer is not booting up it keeps freezing on the ‘Starting Windows’ screen. When I try going into safe mode it seems to get stuck at classpnp.sys.

I’ve tried running Startup Repair from the install dvd, all I get is:

problem event name — startup repair offline

problem signature 01 — 6.1.7600.16385

prob sig 02 — as 01

prob sig 03 — unknown

prob sig 04 — 21201078

prob sig 05 — AutoFailover

prob sig 06 — 13

prob sig 07 — no root cause

OS ver 6.1.7600.2.0.0.256.1

locale ID — 1033

I’ve tried system restore but all I get is:

the file or directory is not a reparse point — 0x80071126

I’ve tried bootrec (all four options)

under ‘diagnosis and repair details’ all sections come up as 0x0 except Chkdsk which has an error code 0x1126. it also says ‘unspecified changes to system config might have caused the problem’ ‘repair — failed 0x3’

My computer is a self build:

Mobo Abit A-S78H (AMD 780G chipset / OB ATI HD3200 graphics)

AMD 64×2 5000+ (stock cooler)

4 Gb ram (Corsair XMS)

Maxtor 160Gb Sata 150

Samsung DVD burner (IDE)

480 watt PSU (XPower)

Windows 7 Pro 32bit

1. Do you have any external USB devices connected to the computer?

2. When was the last time it was working fine?

Disconnect all external devices and then try to restart the computer and check if you are able to log on to your computer. From the problem signatures that you have given it seems that at start up it is trying to load any device whose drivers are not loaded properly.

Try booting into Low resolution video mode it may work if issue is caused due to the display card drivers.

If your computer has a single operating system installed, press and hold the F8 key as your computer restarts. You must press F8 before the Windows logo appears. If the Windows logo appears, try again by waiting until the Windows logon prompt appears, and then shutting down and restarting your computer.

If your computer has more than one operating system, use the arrow keys to highlight the operating system you want to start in safe mode, and then press F8.

a) On the Advanced Boot Options screen, use the arrow keys to highlight Enable low-resolution video (640×480), and then press Enter.

Check if you can boot into Windows.

Hope this helps!

Halima S — Microsoft Support.

Visit our Microsoft Answers Feedback Forum and let us know what you think.

How to Fix Freezing & Other Issues During Windows Startup

What to do when Windows hangs during the startup process

One particularly frustrating way in which your computer might not start is when you encounter an issue during the Windows startup process but have nothing to go on—no Blue Screen of Death or another error message.

Maybe Windows 7 hangs on startup, forcing you to look at «Starting Windows» for an hour. You’re forced to restart manually, only to watch it freeze at the same place again. Or maybe your Windows 10 computer restarts automatically sometime after it begins to load, causing what’s called a «reboot loop.»

Sometimes your computer might even stop at a point where you can move your mouse around but nothing happens. Windows might seem like it’s still trying to start but, eventually, you have to manually reboot your computer, only to see the same behavior again!

If your PC is, in fact, booting to the Windows login screen, you see any kind of error message, or if you’re not even getting past the POST, see How to Fix a Computer That Won’t Turn On for a better troubleshooting guide for your specific problem.

This guide applies to any version of Windows, including Windows 10 through Windows XP.

How to Fix Stopping, Freezing, and Reboot Issues During Windows Startup

Power your computer off and then back on. Unfortunately, you can’t properly restart Windows because it’s not fully loaded, so you’ll have to do it manually.

Many things go on in the background when Windows is starting up. Sometimes things don’t work exactly as they should, especially after Windows has installed updates or there were other major changes to the operating system the last time it was up and running. A restart might be all Windows needs to get back on track.

If you see a blue screen full of information flash on the screen before your computer reboots, this is a Blue Screen of Death and your computer happens to be configured to reboot after one. You can disable this automatic restart if you want to.

That’s right–don’t do anything in Safe Mode, just get in and restart. Like you read in the first idea above, sometimes updates or other things get hung up. If a forced, total restart doesn’t work, try it from Safe Mode. This works more often than you’d think.

Repair your Windows installation. A common reason for Windows to freeze up or reboot automatically during the Windows startup process is because one or more important Windows files are damaged or missing. Repairing Windows replaces these important files without removing or changing anything else on your computer.

In Windows 10, this is called Reset This PC. Windows 8 calls it Reset Your PC or Refresh Your PC. In Windows 7 and Vista, this is called a Startup Repair. Windows XP refers to it as a Repair Installation.

The Windows XP Repair Installation is more complicated and has more drawbacks than the repair options available in the other operating systems. So, if you’re an XP user, you may want to wait until you’ve tried Steps 4 through 6 before giving this a shot.

Start Windows using Last Known Good Configuration. If you’ve just made a change to your computer that you suspect might have caused Windows to stop booting properly, starting with the Last Known Good Configuration could help.

This will return many important settings to the states they were in the last time Windows started successfully, hopefully solving this problem and allowing you back into Windows.

Start Windows in Safe Mode and then use System Restore to undo recent changes. Windows could freeze, stop, or reboot during the startup process because of damage to a driver, important file, or part of the registry. A System Restore will return all of those things to their last working order which could solve your problem entirely.

Depending on the reason that Windows isn’t starting, you might not even be able to enter Safe Mode. Fortunately, you can also perform a System Restore from Advanced Startup Options in Windows 10 or Windows 8, or System Recovery Options in Windows 7 or Windows Vista, as well as from your Windows Setup DVD.

Please know that you will not be able to undo a System Restore if it’s done from Safe Mode or from System Recovery Options. You might not care since you can’t start Windows normally anyway, but it’s something you should be aware of.

A virus or other kind of malware might have caused a serious enough problem with a part of Windows to cause it to stop starting properly.

If you can’t get into Safe Mode, you can still scan for viruses using a bootable malware scanner. See our Free Bootable Antivirus Tools list for a number of different programs that can do this.​

Clear the CMOS. Clearing the BIOS memory on your motherboard will return the BIOS settings to their factory default levels. A BIOS misconfiguration could be the reason that Windows is freezing during startup.

If clearing the CMOS does fix your Windows startup problem, make sure future changes in BIOS are completed one at a time so if the problem returns, you’ll know which change caused the problem.

Replace the CMOS battery if your computer is more than three years old or if it’s been off for an extended amount of time.

CMOS batteries are very inexpensive and one that is no longer keeping a charge can certainly be the cause of Windows freezing, stopping, or rebooting during startup.

Reseat everything you can get your hands on. This will reestablish the various connections inside your computer and is very often a «magic» fix to startup problems like this, especially reboot loops and freezes.

Try reseating the following hardware and then see if Windows will boot properly:

Unplug and reattach your keyboard, mouse, and other external devices as well.

Check for causes of electrical shorts inside your computer. An electrical short is often the cause of reboot loops and hard freezes while Windows is starting.

Test the RAM. If one of your computer’s RAM modules fails completely, your computer won’t even turn on. Most of the time, however, memory fails slowly and will work up to a point.

If your system memory is failing, your computer may power on but then freeze, stop, or reboot continuously at some point during Windows startup.

Replace the memory in your computer if the memory test shows any kind of problem.

Test the power supply. Just because your computer initially turns on does not mean that the power supply is working. While it might not be common for your computer to get all the way to the Windows startup process with a damaged power supply, it does happen and is worth a look.

Replace your power supply if your tests show a problem with it.

Replace the hard drive’s data cable. If the cable that connects the hard drive to the motherboard is damaged or not working, then you could see all kinds of issues while Windows is loading—including freezing, stopping, and reboot loops.

Don’t have a spare hard drive data cable? You can pick one up at any electronics store or you could borrow the one that another drive is using, like your optical drive, assuming, of course, that’s it’s the same type of cable. Newer drives use SATA cables and older drives use PATA cables.

Make sure you’ve tried your best to complete the troubleshooting steps up to this one. Steps 14 and 15 both involve more difficult and destructive solutions to freezing, stopping, and continuous reboot problems during Windows startup. It may be that one of the below solutions is necessary to fix your problem but if you haven’t been diligent in your troubleshooting up to this point, you can’t know for sure that one of the easier solutions above isn’t the right one.

Test the hard drive. A physical problem with your hard drive is certainly a reason why Windows might reboot continuously, freeze completely, or stop in its tracks. A hard drive that can’t read and write information properly certainly can’t load an operating system properly.

Replace your hard drive if your tests show an issue. After replacing the hard drive, you’ll need to perform a new installation of Windows.

If your hard drive passes your test, then it’s physically fine, so the cause of the problem must be with Windows, in which case the next step will solve the problem.

Perform a clean install of Windows. This type of installation will completely erase the drive and install Windows again from scratch.

In Step 3, we advised that you try to solve Windows-caused startup issues by repairing Windows. Since that method of fixing important Windows files is non-destructive, make certain that you’ve tried that before the completely destructive, last-resort clean install in this step.