Windows 7 MBR Issue


I have a problem with booting on Windows 7 disk/MBR, I hope very much i can get some Professional help with this. I have 2 separate physical hard drives. On HD1 I have Windows Vista installed, I then decided to shift to Windows 7 so I installed it as a separate operating system on my second hard drive HD2. It made a boot list where I could choose to boot from Vista or 7, this worked fine. But now I want to get rid of the Vista installation and reuse the hard disk in a nas box after I copied all the data from Vista a need to save. Problem is when I remove the HD1(Vista) the computer cant boot on HD2, it says that its not possible to boot from HD2. I suspect that the MBR that is used for booting was located on HD1(Vista). How can I make it boot on the HD2 without HD1 present, can I create a new mbr on that drive? I tried with the Windows 7 installation disc but no luck. :(

Please explain how I can do this and what commands I should use :confused:, I don't normally do this. and it seems changes has been made in windows 7, it seems it has no boot.ini that I can edit in directly.

Thankx a bunch.


100 ways to do this.

Easiest, without commands, is to remove the hdd you want to remove. Then set the hdd that remains to be the drive bios boots from.

Then run startup repair from the Windows 7 DVD (more than once may be necessary):

Startup Repair - Windows 7 Forums

When it's all done, re-attach other hard drive you removed. Format this drive if you want. All done.


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The short answer is that you are in a very difficult predicament. The good news is that there is a high chance of success in what you are trying to do. However, it is very likely you will need to ensure that HD2 is marked in diskmgmt.msc as Active, Boot, Page File, Crash Dump and Primary Partition. You need to accomplish what you are trying to do by booting into HD2 with HD1 MBR still in place.

Then, read this:

Repair the MBR to restore Windows 7 to your Multiboot Options

Microsoft specifically recommends using the utility VistaBootPro - the only catch is that because it garnered so much success it apparently turned into a commercial product.

A more recent article indicates the following at How to use the Bootrec.exe tool in the Windows Recovery Environment to troubleshoot and repair startup issues in Windows

(You may want to use this utility with the primary Windows 7 drive connected and any traces of the Windows Vista drive offline / disconnected)

  • A master boot record (MBR)
  • A boot sector
  • A Boot Configuration Data (BCD) store
Note When you are troubleshooting startup issues by using the Windows RE, you should first try the Startup Repair option in the System Recovery Options dialog box. If the Startup Repair option does not resolve the issue, or if you must troubleshoot more steps manually, use the Bootrec.exe tool.

To run the Bootrec.exe tool, you must start Windows RE. To do this, follow these steps:
  1. Put the Windows Vista or Windows 7 installation disc in the disc drive, and then start the computer.
  2. Press a key when you are prompted.
  3. Select a language, a time, a currency, a keyboard or an input method, and then click Next.
  4. Click Repair your computer.
  5. Click the operating system that you want to repair, and then click Next.
  6. In the System Recovery Options dialog box, click Command Prompt.
  7. Type Bootrec.exe, and then press ENTER.
Note To start the computer from the Windows Vista or Windows 7 DVD, the computer must be configured to start from the DVD drive. For more information about how to configure the computer to start from the DVD drive, see the documentation that is included with the computer or contact the computer manufacturer.Bootrec.exe options

The Bootrec.exe tool supports the following options. Use the option that is appropriate for your situation.

Note If rebuilding the BCD does not resolve the startup issue, you can export and delete the BCD, and then run this option again. By doing this, you make sure that the BCD is completely rebuilt. To do this, type the following commands at the Windows RE command prompt:
  • bcdedit /export C:\BCD_Backup
  • c:
  • cd boot
  • attrib bcd -s -h -r
  • ren c:\boot\bcd bcd.old
  • bootrec /RebuildBcd

The /FixMbr option writes a Windows 7 or Windows Vista-compatible MBR to the system partition. This option does not overwrite the existing partition table. Use this option when you must resolve MBR corruption issues, or when you have to remove non-standard code from the MBR./FixBoot

The /FixBoot option writes a new boot sector to the system partition by using a boot sector that is compatible with Windows Vista or Windows 7. Use this option if one of the following conditions is true:
  • The boot sector has been replaced with a non-standard Windows Vista or Windows 7 boot sector.
  • The boot sector is damaged.
  • An earlier Windows operating system has been installed after Windows Vista or Windows 7 was installed. In this scenario, the computer starts by using Windows NT Loader (NTLDR) instead of Windows Boot Manager (Bootmgr.exe).

The /ScanOs option scans all disks for installations that are compatible with Windows Vista or Windows 7. Additionally, this option displays the entries that are currently not in the BCD store. Use this option when there are Windows Vista or Windows 7 installations that the Boot Manager menu does not list./RebuildBcd

The /RebuildBcd option scans all disks for installations that are compatible with Windows Vista or Windows 7. Additionally, this option lets you select the installations that you want to add to the BCD store. Use this option when you must completely rebuild the BCD.

Thanks Mike

Well described, it gave a good insight in the different commands to work with the issue. I found out though that "All" that had to be done was to mark the partition on the "HD2" hard disk active (HD1 is not present under this process), then the automatic windows recovery feature on the Windows 7 Installation disc could "See" the operating system and fix the boot problem (I had to run it twice before the problem was fixed)

This is how to mark the Disc and partition active:
At the command prompt, type 'diskpart.' This will get you to the DiskPart prompt, which allows you to use a variety of hard disk partitioning and formatting tools similar to FDISK in older versions of Windows.
At the DiskPart prompt, type 'select disk #' where the # sign is the number of the hard disk drive with Vista installed on it. How do you figure this out? Easy, if your Vista drive is the only hard drive in your computer, it is Disk 0. If you had an original hard disk with another operating system, then added another hard drive and [COLOR=#3e6a8d !important][COLOR=#3e6a8d !important]Windows 7[/COLOR][/COLOR]

later on, then your Windows 7 drive will be 'drive 1' and so on.

Now that you have selected your Windows 7 hard drive, select the partition by typing 'select partition #' where the # sign is the partition that has Windows 7 installed on it. If your hard drive has only one big partition using all the space, type 'partition 1'. Otherwise, the remainder of the partitions on the disk are numbered in sequential order from 1 onwards.
Now that you have the Windows 7 partition selected, type 'active' and press ENTER. The Windows 7 partition is now active. Finally, type 'exit' to close DiskPart. Reboot the computer and reload the recovery environment and run the automatic fix problem feature twice with reboots as needed.

Thankx anyway.

If it were me, I'd be embarrassed to give a bad rating for proven advice that works.

You could have also simply moved the boot files to the active partition on the drive you want to boot from, manually. Then remove the reference to the old OS once booted up.


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