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Seeming as quite a few of the "Related Questions" have answers by me, I am rather embarrassed to ask this, but I hope someone can help. I do have a solution to this problem, however, I would rather not proceed if I can help it.

A friend of a friend gave me a computer to repair that would not boot, I was told that they really want to keep their data but understand if I can't and "do whatever" to repair it.

My first thought before examination, based on talking with the person was hard drive (mechanical) failure.

I started by putting the hard drive in my copier and tried to take a backup (as I usually do for a first step). It succeeded.

I ran a few of my usual tools and they could not find any files or enumerate the hard drive at all. (I checked SMART data and did 2x full surface scans and found no errors what so ever)

Using a custom Windows PE image, I tried basically all the "normal" things, but as (I think) all of the Windows tools (excluding Diskpart) are file system level and not drive level, it was not at all successful. Diskpart was no help (I forget what it actually said).

I then used one of my favourite tools, Testdisk and was able to rebuild the partition table. (I actually mean rebuild, it became corrupt, it was not just deleted or other).

Now, Windows PE can go to the C drive, and I was able to see all the files - and "chkdsk /F" had a field day "fixing" things.

However, whenever I boot, I get the old message "A disk read error has occurred".

I have tried everything I can think of, I have rebuilt the MBR, replaced the bootloader (and options) but I am having no luck.

Also, I used Gparted and noticed a start and end blank block followed by a 5MB partition with an unknown format/partition. I deleted these and stretched the main drive to cover the entire drive.

Startup Repair does not work - it simply just suggests to remove any devices that are plugged in! It did this from the first time and only suggests something different if I use this option halfway through one of manual steps.( e.g. instead of deleting and then rebuilding the menu, if I do it after just deleting, it will automatically remake it - which isn't really any help).

My guess would be that whatever caused this error in the first place took out a boot/critical file, however I would of thought that Windows would boot and fail/bluescreen/other and not have this error. However, there is no repair install and SFC does not work from Windows PE. I am unaware of anything else that can do a file level scan and repair damaged files.

Anyway.... Time is limited I have been trying to fix this for the past 3 days (whilst doing other work... not non stop!), and just been going around in circles. I want to return this machine soon, so I will post the following as an answer if nothing gets suggested or if they do not work:

I have no idea what caused this error in the first place - I have done what the client really wanted and taken a backup of all their files, pictures and more. I am satisfied that the hard drive is not physically (or otherwise) damaged and partition tables do not just become corrupted, I think it must of been a virus and/or a random error. It is not know what else is effected, so I have performed a full format of the system and then copied back all the data back.

Edit- (Basically, this is what I did and it works fine - However, I don't like it getting the better of me and I copied the "broken" image back to the hard drive in order to try and fix it. If I can't come up with anything, I will just do this fix again - However, I am sure a repair must be possible.)

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You lost me at the end a bit. In the end you formatted the drive, installed the OS and restored data to the original drive. You now want to restore your block by block image to a different drive and try to actually repair that partition? I just want to make sure I understand where you are, and what you're trying to get done before I start throwing answers. PS don't be embarrassed, that's lame. :) – Ƭᴇcʜιᴇ007 Feb 11 '10 at 2:50
Sorry... Basically I was trying for a few days with no luck to repair it, so in the end I just formatted and did a new install which worked fine. so - I know I have a working solution and can give back to the person - however, they will still need to reinstall all their programs. It seems like such an easy job and all the usual fixes just didn't work - I have copied the original image back to the hard drive in order to try other solutions as I am sure a fix is possible. If however no one here can help - or I don't manage it, I will simply reinstall Windows again as I know that works. – William Hilsum Feb 11 '10 at 3:00
After you ran CHKDSK /F and it 'fixed' things, could you read any data from the drive? – Ƭᴇcʜιᴇ007 Feb 11 '10 at 3:35
@techie007 I could read files straight after Testdisk repaired the partition table - After this, I took a backup of all the data (separate from the image of the entire drive I did earlier). – William Hilsum Feb 11 '10 at 11:43

This is a tough one for sure, and I'd (as well) call it 'fixed' by the method you got stuck doing. :)

Here's my suggestion/guess, and it's kind of goofy:

Make two copies of the damaged image you backed up; one to the target drive and one to another drive ('spare').

Get the target drive back to how you had it after TestDisk restored the partition.

Do the same to the 'spare' (so you can read all the data).

Try to repair the target using the Windows CD - Hopefully it can recognize the existing Windows and offer some kind of repair that doesn't involve a format. If it offers to let you 'upgrade' the existing Vista install, do that. :)

Once you got it booting in some form (you might want to take a copy), boot off a CD (Win PE or alike) and copy all the contents from the 'spare' to the 'target'.

The hope is that you'll end up with a recovered bootable partition, boot sector and Windows boot procedure on the Target, but with a slightly-screwed up file system. So by copying the files over-top again (form the spare) you may be able to get all the original files back in place, but without messing up the hopefully repaired boot system, and without having to run a chkdsk (which may make things worse in this situation) as the partition table will be properly updated when the files are over-written by the the CD based OS.

Will this work? I doubt it, but I can't think of much you haven't already tried. Again, you've done more than most would already, and the small chance for a full recovery may have already been destroyed by things like SMART, auto-run chkdsks and such, before you even got the computer.

NB: If you haven't tried it already - check out GetDataBackNTFS. It's pay-soft, and I'm not sure it's going to help now, but it's still worth adding to the tool cache for similar situations. Oh and SpinRite if you don't have it. I'm definatly going to check out Testdisk a little more for my own use.

Good luck, let me know how it goes. :)

share|improve this answer
Spin rite didn't do a thing as it isn't the sort of damage that it repairs. I haven't checked GetDataBackNTFS but from looking at the information, I doubt it will help as the files are not deleted, corrupt (visibly), missing or otherwise. I like your idea about reinstalling then replacing files... but I don't think it will work because of registry/updates/service packs... I will try to replace just the boot files though and see if it has any effect. +1 thanks! – William Hilsum Feb 11 '10 at 15:11
It appears this doesn't work. I am rather confused as there must be something else wrong - anything short of a full format and a fresh install looks like it sticks with "A disk read error has occurred"..... If no one else has a suggestion, I will mark yours as answer as it doesn't feel right doing mine after you have tried to help so much (and read my long question!). – William Hilsum Feb 11 '10 at 19:40
Generally dumping files over-top is fine as long as the SP and updates are at least close. :) I think the trick is you're going to need to identify WHAT boot files are corrupted and NOT copy those ones. I can't even imagine how you would establish that though, especially with a known-damaged allocation table. Again I think you got rooked by a SMART or CHKDSK or something remapping a bad block before you had a chance to extract the data (with Spinrite or alike) and you may jus be SOL unless you can magically figure out WHAT it "reapired". :( – Ƭᴇcʜιᴇ007 Feb 11 '10 at 20:38
Maybe trying again, onyl this time format and install Windows from scratch, update it to the latest SP/updates and then copy everything BUT the Windows folder (and leave any boot files in the root), and then inject the regstry into the Windows folder (windows\system32\config)? – Ƭᴇcʜιᴇ007 Feb 11 '10 at 20:47
On top of this though, there is the whole WinSXS folder that will have mismatching data... Installing the registry is one thing, but I am guessing that none of the installed programs will really work after this... Anyway, I will leave this on for a few more days, but will accept your answer if no one else responds. Thanks. – William Hilsum Feb 11 '10 at 21:25

You can use the emergency reset disk, which can be found by searching emergency reset disk on google. You will need to burn the iso to the cd. Then get on your computer and boot to the emergency boot disk. You will get a few options on resetting and fixing your pc.

Also check if you can repair using the Windows vista cd. Boot the Windows 7 installer Disk, choose "Repair", Open the Command Prompt. Enter the following commands:

bootrec.exe /fixmbr bootrec.exe /fixboot bootrec.exe /rebuildbcd

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I searched for "emergency reset disk" and only got 4 results. None of them answered the question. Please try again. – DavidPostill Feb 12 at 14:26

For Missing Operating System or Operating System Not Found you need to boot with the disk, and do some repair, here is what you can try.

Boot the Windows 7 or Vista DVD, choose "Repair"
Open a Command Prompt.
Enter the following commands:

bootrec.exe /fixmbr
bootrec.exe /fixboot
bootrec.exe /rebuildbcd

Hit Enter.

My problem was fixed by doing this steps hope this will help to other people.

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