Modifying the Windows 7 boot loader with the Boot Configuration Data Editor tool

Sometimes dual-booting a system is a handy
way to test new software, either a new operating system, or an
application that needs to be run in a specific version of Windows.
Other reasons to dual boot might include replication of a client
environment.

Windows handles dual booting by using boot.ini to display a menu of
bootable choices or partitions found on the current system. In Windows
Vista and later versions of Windows, the bootloader was moved from
boot.ini to a utility called BCDEdit.

Recently, I decided I could make better use of some disk space thatI
had set aside to create a bootable VHD for Windows Server 2008 R2.
There was no data other than the OS installation contained within the
file because I had only used it to prepare a blog post about booting
from Virtual Hard Disks.To free up the space, I deleted the VHD.

Note: Always make sure to back up any data that you
want to keep before deleting or modifying partitions on VHDs. Your
changes could make the partition unbootable.

Once I had the VHD removed, I thought Windows would be smart enough
to clean up the boot loader, but I was not so lucky. I had Windows 7
set as the primary OS, so I was not without a system.

I started looking around for boot.ini and was directed toward the
Boot Configuration Data Editor (BCDEdit) as the utility to use when
editing boot loader information in Windows 7 (and in Vista too).

To begin, open the Start Menu, select All Programs, and then
Accessories. Right-click on Command Prompt and select Run As
Administrator.

Once in the command window, type bcdedit

This will return the current running configuration of your boot loader, showing any and all items that can boot on this system.

In this example, I decided to remove the entry for my Windows 2008
R2 installation, as I wouldn’t need it for the time being. To remove an
entry, you will need to know the Boot Loader Identifier (found in curly
braces in the image below).

Figure A

I copied the whole list into Notepad and then selected and copied just the ID, braces included.

Removing an entry from the Boot Loader

One simple command got the Windows Server 2008 R2 entry out of the boot loader. At the command prompt, enter the following:
Bcdedit /delete {boot loader identifier}

Press enter and the Boot Configuration Data Editor (BCDEdit) will
remove the entry for the ID you specified and display a message when
finished.

When Windows starts, the only choice available in the boot menu should be the current Windows installation.

Warning: Be careful when editing the boot
configuration data. If you mistakenly remove the current instance of
Windows, you may render your computer unbootable.

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