Preparation

The first thing one needs to do is to create a new partition on which to install Windows XP. This you can do by going to Computer>Right click>Manage>Disk Management.

Now right click on the blue primary hard drive at the bottom section of Disk Management and select "Shrink Volume". You can then choose how big the new partition that you want for Windows XP should be. It's suggested that you take into account that you may want to install programs and save data there, but also that you do not limit the amount of space available to Windows Vista unreasonably. Your total hard drive size will be your ultimate guide in selecting the amount of space you allocate to each operating system.

Shrink your Vista Partition---Unallocated Space
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After the primary partition has been shrunk you will have Unallocated space visible in black. At this point it is recommended that you change the drive letter of your DVD drive by inserting a DVD or CD into your DVD drive and close Autoplay when that dialog box appears, right click the blue area of your DVD drive in Disk Management and select "Change drive letter and paths..." and click Change. From the drop down menu on the right of the dialog box that appears, select E and click OK, and then click Yes when you asked to confirm your action. Now remove the CD or DVD from your drive.

Change your drive letters


Changing the drive letters as above leaves your drive/partition structure in a less confusing form than having your hard drive partitions irregularly lettered and does not interfere with the functioning of your DVD drive in any way. You will now have drive letter D: available to use for the partition you will create for Windows XP.

It is now time to create your Windows XP partition from the unallocated space by right clicking the unallocated space and selecting "New simple volume". Follow the "New simple volume Wizard" and accept the defaults until you get to the point where you can insert "Volume label" and type XP there to make identification of your XP installation drive easy. At this point select "Quick Format" to speed the process and continue with the wizard to completion of this action.

Create a new partition


NB. At this point it is critical that you close Disk Management and restart your computer so that your changed disk/drive structure is taken fully into the Windows Vista configuration settings. After your system has restarted, you will again need to restart your system to finalize the setting up of your new partition.

Reboot twice to set
your drive configuration



Install Windows XP

Once you have completed the preparation, you can now insert your Windows XP setup disc and restart your system again to boot from your XP CD and install Windows XP in the normal manner.


Create a Vista Dual Boot Menu

At this point you will have lost your ability to boot into Windows Vista for the time being and the next stage of this excercise is devoted restoring a dual boot to both Windows Vista and Windows XP.

Once you have your XP installation and drivers all installed, download and install VistaBootPRO. Make sure you follow the prompt to install .Net Framework 2.00 as VistaBootPRO will not run without it.

Open VistaBootPRO, ignore the prompt to backup your BCD. Go to the System Bootloader tab, select "Windows Vista Bootloader" in the first section and "All Drives" in the second section and then click Install Bootloader . Next, go to the Diagnostics item on the menu bar and select "Run Diagnostics". VistaBootPRO will default back to the Manage OS Entries page and you will see that you now have entries there for "Earlier versions of Windows" as well as "Microsoft Windows Vista".

Install the Vista bootloader


Restart your system and select the operating system you would like to boot to.

The Vista dual-boot menu