How to create a seperate system partition for dual booting Windows Vista and Windows 7

Applies To: Windows 7

This article describes how to create a separate System partition and configure the boot environment to start both Windows Vista® and Windows® 7. The System partition is the disk partition marked as Active and contains the boot files used to start Windows. Windows Vista is usually installed on a disk partition that is marked Active. Installing Windows 7 to a new partition on the same disk does not change the Active partition. However, creating a system image backup from Windows 7 includes critical boot files from the System partition, which may also include Windows Vista files. Using a disk configuration with a separate System partition for boot files supports a multiple boot configuration and allows a system image backup of Windows 7 without Windows Vista files.

In this article, assume that Windows Vista is installed first in Partition 1 and Windows 7 is installed at a later time on a separate partition, (Partition 2). Partition 1, containing Windows Vista is marked Active and is the system partition. During installation of Windows 7, the Windows 7 boot files are copied to the System partition which also has the earlier version of Windows.

Logon to an Administrator account in Windows 7 and use the following steps to create a new System partition containing only the files required to boot Windows 7 and Windows Vista. In this article, when logged on to Windows 7, the partition containing Windows 7 (Partition 2) is assigned drive letter D:, and the partition containing Windows Vista (Partition 1) is assigned drive letter C:.

This process requires the following steps:

  1. Review the current boot configuration (BCD) before changing the system partition.

  2. Use Disk Management console to create a new primary disk partition from unused disk space for the new System partition.

  3. Mark the new partition as Active.

  4. Use bcdboot.exe to copy the Windows 7 boot files to the new System partition.

  5. Reboot to Windows 7 to establish the new system partition.

  6. Update the boot configuration to include Windows Vista by importing the previous boot configuration data (BCD).

  7. Update the Windows Boot Manager device to the new System partition.

  8. Reboot the system and verify both Windows Vista and Windows 7 can boot using the new System partition.

Important

When you are asked to enter a command at the command prompt, be sure to use a Run as Administrator command prompt for elevated permissions.

Review the current boot configuration (BCD) before changing the system partition.

  1. Use the bcdedit command with no arguments to view the current boot configuration.

The bcdedit output will be similar to the entries shown below. Verify the value of the drive letter assigned to the device for each boot entry corresponds to the Windows operating systems installed on the system. Look for the element partition=<letter>.

Windows Boot Manager 
--------------------
identifier              {bootmgr}
device                  partition=C:
description             Windows Boot Manager

Windows Boot Loader
-------------------
identifier              {current}
device                  partition=D:
path                    \windows\system32\winload.exe
description             Windows 7

Windows Boot Loader
------------------------
identifier              {358e1d8e-3bcf-11de-a57b-9ab47e0f3928}
device                  partition=C:
path                    \Windows\system32\winload.exe
description             Microsoft Windows Vista

Use Disk Management console to create a new primary disk partition from unused disk space for the new System partition.

  1. Use 200MB of free space on an existing partition and shrink the partition.

  2. Create the new primary partition, and format using NTFS.

  3. Assign the drive letter, S:.

Mark the new partition as Active.

  1. Right-click on partition S:, and select Mark partition as Active.

Use bcdboot.exe to copy the Windows 7 boot files to the new System partition.

Execute the following command: Bcdboot D:\Windows /s S:. Bcdboot copies the required boot environment files for Windows 7 to the S: partition, and creates a new BCD store to boot Windows 7 from the D: partition. The new BCD store does not have a boot entry for Windows Vista after this step.

Reboot to Windows 7 to establish the new system partition.

A reboot is required for the BIOS to recognize the new Active partition. When the system reboots, there will be no boot menu as the boot configuration only has a single entry and automatically starts Windows 7.

Update the boot configuration to include Windows Vista by importing the previous boot configuration data (BCD).

  1. The previous boot configuration reviewed in Step 1 has boot entries for both Windows Vista and Windows 7. Use the bcdedit command to import the previous BCD store located on C: to the new System partition, S: as follows: Bcdedit /import C:\Boot\BCD.

  2. Check the updated boot configuration using bcdedit, as in Step 1). The output will look similar to the following:

    Windows Boot Manager 
    --------------------
    identifier              {bootmgr}
    device                  partition=C:
    description             Windows Boot Manager
    
    Windows Boot Loader
    -------------------
    identifier              {default}
    device                  partition=D:
    path                    \windows\system32\winload.exe
    description             Windows 7
    
    Windows Boot Loader
    ------------------------
    identifier              {358e1d8e-3bcf-11de-a57b-9ab47e0f3928}
    device                  partition=C:
    path                    \Windows\system32\winload.exe
    description             Microsoft Windows Vista
    
  3. The Windows Vista boot entry is back and the Windows 7 entry is the same as earlier. However, after importing, the device for the Windows Boot Manager entry refers to the old System partition C: and needs to be changed to refer to the new System partition.

Update the Windows Boot Manager device to the new System partition.

  1. Execute the following command: Bcdedit /set {bootmgr} device partition=S:.

  2. Verify the boot configuration again to verify the Windows Boot Manager device is the new System partition, and the Windows Boot Loader entry for each version of Windows refers to the correct volume. The bcdedit output will be similar to the following:

    Windows Boot Manager 
    --------------------
    identifier              {bootmgr}
    device                  partition=S:
    description             Windows Boot Manager
    
    Windows Boot Loader 
    -------------------
    identifier              {current}
    device                  partition=D:
    path                    \windows\system32\winload.exe
    description             Windows 7
    
    Windows Boot Loader 
    ------------------------
    identifier              {358e1d8e-3bcf-11de-a57b-9ab47e0f3928}
    device                  partition=C:
    path                    \Windows\system32\winload.exe
    description             Microsoft Windows Vista
    Earlier Version of Windows
    

Reboot the system and verify both Windows Vista and Windows 7 can boot using the new System partition.

  1. Confirm the Windows Boot Manager shows a boot menu that includes entries for both Windows Vista and Windows 7.

Note

Since the Windows Vista partition no longer contains critical boot files, it will no longer be included by default in a system image created from Windows 7. However, the Windows Vista partition can still be optionally included via the Create a system image task from the Backup and Restore Control Panel.