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Unmountable Disc Volume - Windows 10

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Unmountable Disc Volume - Windows 10

Just had a call from my daughter
Her laptop which she had upgraded to Win 10 now fails to start due to an unmountable disc volume
This is something I haven't come across before - any advice on the steps to recover
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Re: Unmountable Disc Volume - Windows 10

On another computer (not one running Windows 10 in its first 30 days, ideally) use Microsoft's Media Creation Tool http://windows.microsoft.com/en-gb/windows-10/media-creation-tool-install to create a bootable disc or USB stick for Windows 10.
Work out how to boot from it (by pressing a function key that depends on the manufacturer or changing the boot order in BIOS).
Boot from the media and enter your language.
When you get to the Install Windows screen DON'T but select the 'Repair your computer' option at the bottom left of the screen.
Find your way to the Command Prompt option (which is a screen or two in).
When we get to the Command Prompt it will say X:
More to follow in Part 2
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Re: Unmountable Disc Volume - Windows 10

I did wonder about creating an installation disk or USB stick using this http://windows.microsoft.com/en-gb/windows-10/windows-10-recovery-options
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Re: Unmountable Disc Volume - Windows 10

Part 2
Okay, we have booted from a disc/stick and got to the Command Prompt.
The drive lettering under these circumstances differs from normal.  C is often the System Reserved partition used for booting and D: is the drive on which Windows is installed but your computer manufacturer might have thrown in more partitions that are normally hidden.
In the Command prompt type chkdsk c: /f and press enter.  If there is a question answer in the affirmative.  Chkdsk should run on the C: partition and finish quickly because it's small.
If you get a message to the effect that the C: partition cannot be found then you are in real trouble.
If chkdsk reports that it fixed anything try restarting the computer (with the bootable media removed).
If not, perhaps repeat the process for the D: partition and so on until you run out of partitions.
If the computer still fails to start we move on to using the bootrec tool: https://support.microsoft.com/en-gb/kb/927392 ;  
The difference between an installation disk and a recovery disk is that the former lets you install as well as recover and, for most versions of Windows, is not readily available.  I always use an installation disk because I need to keep a stock of those anyway and I know not to install when all I need is the recovery options.
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Re: Unmountable Disc Volume - Windows 10

As we don't have an option for accessing a Win 10 PC would the link I gave above do the job
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Re: Unmountable Disc Volume - Windows 10

You don't need a Windows 10 PC (in fact you want to avoid using one if possible).  The link I gave would probably be easier than yours but any Windows boot disc would do at this stage, even an old XP one.
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Re: Unmountable Disc Volume - Windows 10

I am a bit puzzled - from your first post I assumed that you needed to create a Win 10 repair disc
I have loads of Windows installation  disks
XP, Vista, Win 7 so would it be better to start with one of those
Heck I even have a Bart PE Boot disk
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Re: Unmountable Disc Volume - Windows 10

I'm not sure what the problem is but it is likely to be something to do with the System Reserved partition that contains the boot information.  First we should check it for file corruption and you can do that with any disk that will allow access to the chkdsk utility.  If that doesn't work we will need o try the bootrec tool.  I presume at that stage we need a Windows 10 disk.
Did your daughter do anything to provoke the problem.  I have read about a similar issue that can arise after a Reset if this is done soon after the upgrade.  There doesn't seem to be a cure for that one.     
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Re: Unmountable Disc Volume - Windows 10

Quote from: Oldjim
Heck I even have a Bart PE Boot disk

I'd probably go with the Bart.
With luck, all you need to do is do a chkdsk on the partitions to mark them 'clean' and all will be good.
If that doesn't work you're probably going to want a Windows 10 disk/usb and do the start up repair route.
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Re: Unmountable Disc Volume - Windows 10

Any progress on this, Oldjim?  The three bootrec commands you might wish to try if your get to that stage are 'bootrec,exe /rebuilldbcd' ,  'bootrec,exe /fixmbr' &  'bootrec,exe /fixboot'.  I'm a bit hazy about which is the best order (as stated?) and whether it is worth trying one at a time then rebooting to see if it has worked or piling in with all three.
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Re: Unmountable Disc Volume - Windows 10

Latest situation is that the hard drive is in such a state that nothing works
I will pass on your latest suggestions
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Re: Unmountable Disc Volume - Windows 10

Hold on.  The hard drive could be 99.9% dead and so long as the computer still knows that it's there you should be able to boot from external media and run chkdsk.  But if chkdsk throws up a lot of errors or gets so far and then virtually stalls then the hard drive could well be close to death and priority should switch to salvaging anything that isn't backed-up whilst imposing the minimum extra stress on the hard drive.
Provided the problem arose a while after the upgrade then it should be relatively simple to replace the hard drive and reload Windows 10 - if that is what's required.
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Re: Unmountable Disc Volume - Windows 10

I have asked my daughter to bring the laptop to me and I will try to get the documents etc. off it by networking it onto my computer
Once I have done that I will have a play
Thanks for your help
One question - where is the registration data stored as by replacing the hard drive and loading 10 there won't be any record on the laptop and I don't believe that she has a linked Microsoft Account
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Re: Unmountable Disc Volume - Windows 10

The registration is linked to the hardware, principally the motherboard, so you should have no problems re-activating if you replace the hard drive provided Windows 10 was activated the first time round.  
Edited to remove some extra stuff I now think was wrong.
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Re: Unmountable Disc Volume - Windows 10

Thanks
I will now wait until I get the laptop and see what I can do