Unmountable_boot_volume

[djprescott]

Had this error message come up yesterday when booting up my computer. Running Win XP Home SP2. Any ideas what the problem is?
Problem occurred after Google Earth update failed to install and I had to turn m/c off via the on switch. Would not let me close down windows.

[rojash]

Sounds to me like a failed/failing hard drive - in other words, the failure to install and shut down were symptoms rather than the cause of your problem.

You could try running a repair install, but even if that works, I would suggest that you then backup and replace the hard drive.

[vehelpfulguy]

When a PC first starts up it has no idea which devices contain an operating system such as Windows, and which device to "boot " from.

There could be an operating system on diskette (honestly), hard disk or CD or DVD.

So the PC looks on each of these devices, one at a time, trying to find a file that identifies itself as a "boot" volume.

If the PC cannot find any device with the "boot" file then you will get a message like you have got.

This may be for a number of reasons.

One reason may be that the "bios" in the PC has "lost" the device (so the PC does not even know the device, say hard drive, is even there).

Another reason may be that although the device, such as hard disk, is there, maybe the "boot" file has become corrupt or deleted so the PC is not able to boot from it.

More....

[vehelpfulguy]

As you can see, it all gets rather technical and dificult to fix.

You could try to go into the BIOS and verify if the hard disk on the PC is listed as a being available.

(Watch as your PC starts up and you get a brief message saying something like "press xxx to go into the BIOS". Read the documentation if you are not sure).

When you are in the BIOS find a list of the devices and see if the hard disk is listed.

I had a similar problem to this a few weeks ago after doing a Microsoft update, my PC would not boot afterwards. I tried everything but in the end gave up and had to reinstall Windows.

Luckily I had a complete backup of my hard drive and was able to recover in about 10 minutes.

In your case you may not be as lucky and it may mean a new hard drive, or a reinstall of Windows on this hard drive, which means you will lose everything.

Let us know if you need more help.

[djprescott]

Thanks for the responses.
I have checked the bios and it all looks ok to me. As I turned the m/c off whilst it was trying to install, I would think the logical explanation is a corrupt boot file.
Can this be repaired by running chkdsk/r?

[rojash]

I can't follow your reasoning as far as the cause of corruption is concerned. There is no reason for any of the boot info to be modified during an application update or install, so no reason for it to become corrupted if you interrupt the process.

You can attempt a repair by following the instructions here:

http://support.microsoft.com/kb/555302

If you get the machine working, I strongly suggest that your next task is to ensure that you have a full backup

[Kerplunk]

Only re-install windows as a last resort. Try using the recovery console as in rojash's post, but use it to rebuild the Boot.ini file. Works every time for me (Except in the case of hardware failure)

[djprescott]

Thanks for all the helpful replies.

Just a question:

If I try to start in safe mode, it lists on screen a number of drivers etc before it stops and goes into the 'blue screen'.

Does this mean it is likely to be a corrupt boot file or a failing hard drive?

Cheers

[rojash]

It's impossible to say without further investigation. However, in my experience the symptoms you describe will 99 times out of 100 indicate a failing hard drive. The fact that it blue screens could indicate a corrupt driver file, and once again the corruption could be caused by a fault in the hard drive.

[djprescott]

Thanks for all replies.

I successfully ran chkdsk/r as per Microsoft article and it does seem to have repaired the boot file and all seems well now.

Have backed up the drive obviously in case it is a failing hard drive.

Thanks for the help.