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I had another Windows on drive C. Now I have Windows 7 on drive D. I tried to delete all files and folders or format drive C, but my Windows 7 didn't let me. So I inserted booted in the Ubuntu live-CD, deleted all files and folders in drive C without any problems. Then I mistakenly started to format drive C in Ubuntu, but I cancelled it. However I now get this error in a black screen:

Reboot and Select proper Boot device or insert Boot Media in selected Boot device and press a key

I thought that uncompleted format in Ubuntu caused it. So I booted from a Windows 7 disk and from there I reformatted the C drive successfully, but I still get the same error. Any ideas?

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I also have tried system restore from windows seven disk.But it can't find any OS on the hard disk. – arman_aegit May 28 '12 at 12:10
Does system restore see the drive that Windows is on? If not, you'll need to load the appropriate driver. – David Schwartz May 28 '12 at 13:04
did it ever occur to you that there was a reason why windows 7 was not letting you delete your files ? formatting was not the mistake deleting the stuff was enough – Shekhar May 28 '12 at 13:30
up vote 3 down vote accepted

The former C drive contained the boot manager for the hard drive. When you installed Windows 7 on D, it modified that boot config to boot off the windows installation on the D partition. When the format of C started, it wiped out the boot mgr. You can recover booting by creating a small C partition (10MB is fine), then boot the Windows 7 install disk to recovery mode. From there you can restore the boot manager and then edit the boot configuration to point to the D install. The former C partition space can be reused for either a new partition, or resize the to fill that space.

From the Windows 7 Install disk, pick "repair your computer" and then from the menu "Command Prompt". At the cmd prompt, enter

bootrec.exe /fixmbr

(on XP, its "FIXMBR")

Then make sure the C partition has a valid boot manager:

bootrec.exe /fixboot

Then scan the hard drive for valid installs (in your case, there is just the D) and automatically set up the boot configuration:

bootrec.exe /rebuildbcd

Then reboot.

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Now I have a 14 GB free C drive.Can you please explain how to restore the boot record with MBR and edit the boot configuration to point to the D? – arman_aegit May 28 '12 at 13:35
Added steps to fix the boot manager and make sure the boot record is ok (what I previously refered to as MBR). – jdh May 28 '12 at 16:57

The master boot recorder from C drive has been gone with the format action.

To re-enable your MBR, go to windows 7 installation disk, there will be a start-up repair.

If the disk couldn't find your OS, press Shift+F10, CMD windows will appear, find out your drive that has the OS installed this will be something different in your OS.

Assume D is your partition that has the OS, type the following command: bootsect /nt60 D: /mbr /force, restart your computer.

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MBR != boot record. If the MBR was gone, the partition table would be, too. – Michael Kjörling May 28 '12 at 13:41
According to it's message : "Bootcode was successfully updated on all targeted volumes." It was successful.But when I restart , I see that error again ... – arman_aegit May 28 '12 at 13:58
@Michael You are right, that's my mistake :D – Nam Phung May 28 '12 at 14:08
@Arman-aegit: are you sure that you typed the right drive? – Nam Phung May 28 '12 at 14:19
In CMD I changed to D: .Then I typed dir and I saw my windows seven files and folders.It had windows , windows\system32 , program files etc. – arman_aegit May 28 '12 at 14:27

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