Dual booting any Windows operating system has always had to follow a set plan; and that plan, simply put, was 'the oldest operating system 'must' be installed first, followed by the newest operating system.
This has been the time honoured tradition until the release of Windows Vista. Because Windows Vista has a totally different boot loader to previous versions of Windows, it is now possible, with a little help from a third party freeware application called VistaBootPro, to actually install Windows XP on a machine that already has Windows Vista installed.
The instructions below show you how to create a dual boot system between Windows Vista and Windows XP.
For simplicity we are going to use the scenario whereby your PC already has Windows Vista installed. If this is not the case, it is a simple matter to install Vista first onto your PC and then follow the steps outlined below.
To create a dual boot system you require two sperate partitions on your hard drive, or else two separate hard drive. Now as most PC manufacturers' allocate all the space on a single hard drive for the use of Windows Vista it means that before you can proceed to install Windows XP you are going to have to shrink the main partition and then create a new partition from the available free space. So to do this proceed as follows.
1/ Boot your PC to Windows Vista
2/ Click the Start button and then Right Click on the Computer option
3/ From the Drop down menu that appears, select Manage followed by Disk Management
4/ In the Disk Management window, Right Click on the Primary partition (coloured blue) of the hard drive graph at the bottom of the Disk Management window and, from the drop down menu, select the Shrink Volume option
5/ The Shrink Volume wizard will now appear
6/ As you go through the wizard you will be asked by how much you wish to shrink the main partition. Assuming you also want to be able to install programs on the XP partition, try allocating between 10 to 15GB (or more if you have the space) for the XP partition. If you are using Vista Home Premium or above, you should also ensure that the final Vista partition is no lower than 40GB, preferably more.
7/ After you have shrunk the main primary partition by the required amount you will be left with the primary partition (containing Vista) and a section of 'unallocated' or free space. It is in this unallocated space where you now will create a partition in which to install Windows XP
8/To create a new partition, Right Click on the unallocated space and, from the drop down menu, select Create
9/ Follow the Create Partition wizard through and allocate all of the unallocated space for the new partition.
10/ Once the new partition has been created, Close the Disk management window and Reboot your PC
11/ This Reboot changes the configuration settings within Windows Vista. In order to complete the finalisation of your new partition as soon as your PC has booted to the desktop reboot your PC again.
12/ As the PC reboot quickly insert the Windows XP CD into your CD-ROM
13/ XP will now begin the installation process. Continue to install XP making certain that you install it to the New partition you created
14/ Once XP has been installed and the PC has rebooted you will no longer have access to Windows Vista (this is because the Vista bootloader has been over written by XP's boot.ini file) Instead you will boot directly to Windows XP
15/ At this point proceed as if you were only installing XP. Set up your Internet Connection, Firewall, Anti \virus etc and then download any available updates. Some updates you will not be able to download until XP has actually been activated but, for the present, activation of XP can wait.
16/ Once you have updated XP with the few available updates, download and install the third party freeware application called VistaBootPro
17/ VistaBootPro requires .NET Framework 2.0 for it to run, so make certain, when prompted by VistaBootPro setup, that you install the .NET Framework 2.0 prior to installing VistaBootPro
18/ Once VistaBootPro has been installed open VistaBootPro. You will be prompted to back up your BCDedit files, but you can ignore this.
19/ Once VistaBootPro is open, Click on the Boot loader tab and then Select the 'Reinstall the Vista boot loader' option, and Press OK
20/ The Vista boot loader will now be installed
21/ After the boot loader has been installed, Click on the Diagnostics option on the main toolbar and Select the Run Diagnostic option
22/ After the diagnostic program has run (which should take a few seconds) you will default back to the Manage OS Entries page
23/ On this page you should see Two entries:
The Earlier versions of Windows option is where Windows XP will be. You can change the wording of this option by clicking on the Earlier Version of Windows and then putting a check mark in the 'rename selected operating system' option. A new dialogue box will appear where you can type the new name. For simplicity it is better to rename it to Windows XP or something similar.
24/ All that is left to do now is Restart your PC
25/ When the PC restarts you will be presented with a menu giving you the option to boot into either Windows XP (Earlier Version of Windows) or Microsoft Windows Vista
26/ Select the operating system you want to boot to and Press Enter
27/ Your selected operating system should now appear on your screen
28/ Finally, you have 30 (Thirty) days before you need to activate your copy of Windows XP. Make sure XP is working as it should be before activating the operating system; even if this means delaying activation for 10 to 14 days. Once you have activated XP, remember to visit the Windows update site to download any remaining updates for Windows XP
Windows XP does have a problem with Windows Vista's shadow copy feature. This basically means that, when you boot into XP, all system restore points and shadow copies on Windows Vista will be deleted. This is a known problem and one, unfortunately, that Microsoft will not repair. If you are using Windows Vista Ultimate or Enterprise editions you can use Bitlocker Encryption to stop this from happening. Alternatively you could also use a third party boot manager instead. Another option is to image your hard drive, using third party imaging software, such as Acronis True Image. This will back up all of your hard drive and keep everything safe. By using the incremental back up image on a regular basis you will find that Windows system restore points will not be needed. If any problems occur you can simply re-image your hard rive using the last acronis image of the drive.