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I am not sure what has happened! I went on holiday and left with nothing wrong. I came back, started work and overnight the external hard drive packs up! Of course I had every intention of backing it up when I buy a new drive this year (seeing as the previous one wasn't so old at all).

Then the PC packs up when I come home from buying the hard drive. I am getting a blue screen every time I switch it on but being Windows 7, I cannot catch the error message before it reboots.

When it reboots, it asks me if I want to revert to last best known state. I do that but it still doesn't want to work.

I am at a complete loss. I have antivirus and my firewall is switched on.

The only thing I did with the hard drive when I got back was move it (when it was off) so that I could clean my desk.

The PC I bought in September 2012 so it is not that old and the external drive in about May 2011 which is also not that old considering I have another machine that I have had for years and years now and it is STILL running!

Any thoughts/solutions would be appreciated.

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Go into the "system" cpl applet, choose "advanced system settings", on the "advanced" tab, click the "settings" button under the "startup and recovery" section, and uncheck "automatically restart" under "system failure". This will allow you to see the STOP error. Hard-reset the computer (hold power button 4 seconds) to restart. As a humorous aside: MS introduced this little "feature" in windows XP and then said "no more blue screens" in their marketing. They neglected to mention the blue screens still happen, they just cut the power before you can see it. – horatio Jan 4 '13 at 19:41
He cant finish booting unless I read his answer incorrectly, so these instructions wont be of much use to him yet. – francisswest Jan 4 '13 at 19:44


Start by unplugging every external device that is not needed. Leave the keyboard, mouse, monitor connected and try booting. We want to rule out for instance, the external hard drive being accessed by the system, and failing.

Next, run a hdd scan on the internal drive (something like DFT (drivefitnesstest) or seatools, both free) then run a memory test.

Alternatively, and something that will help us further answer your question, when attempting to boot, mash F8 to get the Windows startup menu to show up. Select the "Disable automatic restart on system failure." Then, when it BSODs again, write down the bsod code and bring it back to us. It could give us a next place to look.


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Thanks Francis, I will give that a shot and get back to you. – SixfootJames Jan 4 '13 at 20:35
Hi Francis. Your solution worked and I was able to get to the BSOD. Here is the code. 0x0000007B (0xFFFFF880009A97E8, 0xFFFFFFFFC0000034, 0X0000000000000000, 0X0000000000000000). Phew...hope that's right. – SixfootJames Jan 4 '13 at 22:00
If I try boot into safe mode, the files it runs through is super slow, then bombs out at classpnp.sys? – SixfootJames Jan 4 '13 at 22:24
James, Im assuming you have another computer (typing to us with magic?) so I would HIGHLY recommend you get a hard drive testing tool like DFT (Drive Fitness Test) or Seatools. Both are free and can be burned to a CD to run at boot. These will check to make sure the hard drive is in good condition. the 0x07b errors are usually "Inaccessible boot device" problems. That could be (in my mind) 2 things, either a dying/dead hard drive, or a nasty boot sector virus/rootkit. Is the hard drive clicking or making any unusual noises? – francisswest Jan 4 '13 at 23:37
Hi Francis. Typing from my phone but yes, I have another PC where I can download DFT. Drive is not clicking and it's a relatively new PC. Not sure about viruses as I always scan anything I download and open and my antivirus is always up to date. What is freakishly odd is that first the external drive stopped, and now the internal OS drive. Both of which I think are relatively new. Will try your solutions first. Thanks again. – SixfootJames Jan 5 '13 at 6:47

BSOD are commonly caused by hardware malfunction or software error. In the first case it is usual to just unplug all the USB devices and try to power on the computer. If again it doesn't open the case and clean it inside. Also check all the connections of the cable if everything is bolted down just fine. Then check if it runs if not then maybe it is a software error.

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Thanks gsiotas. I will try this too and get back to everyone. – SixfootJames Jan 4 '13 at 20:37

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