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UNMOUNTABLE_BOOT_VOLUME  on SATA DRIVE - CHKDSK /r now working very well... help!

I got the "UNMOUNTABLE_BOOT_VOLUME"  Message when I boot to safe mode on My Dell SATA 400GB HDD as written below,
"Error message: A problem has been detected and windows has been shut down to prevent damage to your computer. UNMOUNTABLE_BOOT_VOLUME"

I ran hard drive diagnostics from Dells Boot Partition and got the following result.
 Error Code: 0F00:0244 MsgBlock:6528484 Uncorrectable data error

I then booted with my XP cd and did a chkdsk /r from the Recovery Console.
Chkdsk is running super slow, it go to 59% after 10 hours and has been stuck at 59% for another 10  hours.
Will it be harmful if I unplug the system to get out of chkdsk /r or is there a better way to get out of chkdsk when it hangs or is just super slow like this?

Watch Question

There is always a risk in corrupting the disk more if you just "Turn it off". If you can wait, then give it a few more hours. See if it gets past 59 at all. But if it shuts off or you shut it off, then instead of trying the chkdsk again from the dell, I would take the drive out of the computer, and connect it to another, see if you can back up the data, THEN run diagnostics on it.

Also you might want to try a BARTPE disc. http://www.nu2.nu/pebuilder/ 

One other trick to get it past the error (if you want to get really geeky) is to put the drive in a ziplock bag and throw it in the freezer for 24 hours. See if you can get your data off the drive after.

Let me know what happens.


The problem is it is going really slow.  When I entered the Recovery Console, the response was slow at the DOS promt as well.  So. I get the feeling this is going to get worse not better.

My concern is if I let it go longer, when it gets to 100% , does not a chkdsk /r do a 4 pass process?
In other words, does it make a difference when I hit the reset button to get out of a  CHKDSK /R process?


I have been at 59% now for 12 Hours.
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I would slave the disk, and start the data recovery process immediately, ad do no further testing as it will only get slower.....

EasyRecovery Professional - Trial Edition  (you can scan for free, and purchase if you like what it finds...)

GetDataBack Data Recovery Software

And when slaving the drive, you might need to take ownership of the files to gain access....

How to take ownership of a file or folder in Windows XP

There also is another great utility called HDD Regenerator.  I believe it used to be free, then now switched to shareware.  It will scan the drive and mark any bad sectors while moving the data.

I've had mixed results.  One time it ran, did its thing and I was able to copy the files I got stuck on (windows CRC error, file(s) would not copy) and recently, I ran it and it knocked out the drive.  After running it the drive would not boot into windows normally.

A hard drive that's experiencing these problems sounds like its really going to fail very soon.  Discontinue trying to run scans on it and try to copy important data from it.



I pulled the plug on CHKDSK /r in System Recovery at the 24 hour mark. It was at 59% for 12 hours.

I moved the drive to another system and it detected it but wanted to format it.

I then used my SPINRITE FREE DOS BOOT DISK, and it detected it and immediatly determined it was in a very compromised state.  Spinrite then tried to do data recovery... after 5 hours it had detected many bad sectors and was successful repairing some of them.  THE PROBLEM WAS IT WAS GOING TO TAKE 2000 hours.  So I stopped it and have now put it in the freezer.  

How do the other drive recovery utilities match up against Spinrite?

Easy Recovery is very good.  It has a few different methods for data recovery.  However, since many programs have tried to scan/read the disk, and its failing.. the chance for data recovery is declining.

You could also try using Test Disk to scan for the partition and if the partition is found, it will re-write the info to the media descriptor and the drive will be accessible from windows again  link: http://www.cgsecurity.org/wiki/TestDisk

I would try using a boot cd such as Knoppix or BartPE to attempt to copy files off the drive.

Normally, if you run a few disk scans and things look 'weird'  STOP and use a boot CD to attempt data recovery.  As each attempt after that can only worsen the condition.
Don't go tools here.
Hope you have your stuff backed up and warranty is in place.
This drive seems to be very dead.

If the backup is in place, then you might want to try a full swipe of the drive and see what happens, but my guess is that this drive is a goner.
I have a couple XP utility discs that I use in different instances. It all depends on what's wrong with the drive. I have had success with one program, then move it to another situation and it would fail miserably.

If the drive in the Freezer idea works, then Just attempt to remove as much as possible. Don't try to do a chkdsk or anything. It might corrupt more data than needed.

Also make sure that ziplock bag is sealed tight and the freezer is not going to frost the bag in 8 hours. We don't want condensation in the drive.

Let me know what happens.


Is there an optimal Freeze time?  How long do I need to let it un-freeze when I take it out?
For the purpose of moving data to another drive, what is the best program to do that with?
For moving data, you can use BartPE to create a boot cd that has a Windows GUI complete with networking.  Or you can go with Knoppix which after some light setup can copy files from one computer over the network to another.

Most people do 24 hours. Just watch the connections - wipe them off if there is condensation - and dont put it in a really hot room.

Usually I have a cool little device that will connect the drive up via the USB port. I can then just use windows explorer to copy. Otherwise I would try to use Acronis or (if I am confident it will work) Symantec Ghost to copy over the data.

Usually I take a superextend cable and dump the drive in a bag in the freezer and boot the thing after an hour or less. I want to keep the drive cool as long as possible, so I leave the drive in the freezer and immediately begin copying files.

Build a config with a good HDD so you can test what you need to do first. That will save time on the real drive. And as already mentioned a few times, use an OS on CD like BartPE, Knoppix or UBCD. You don't want to boot to this drive again, since that will start Random Access which can make things worse. Just a stream to copy everything and hopefully you're fine.