Befor to start this task, make a complete backup of your system. I will recommend Acronis True Image for this task. In addition do make sure that win2k/xp has drivers available for your hardware. This is especially important if you have a laptop. If there are no drivers available, you are wasting your time.
To start we need to create a partition in which to install win2k/xp. Open disk management; start>run and type in “diskmgmt.msc” without quotes. Hit enter; this brings up disk management. Right click your drive and choose shrink from the menu. I would make the partition approx 10gig for win2k and 15-20gig for XP [depending on how much software you are going to install] Once you have completed the shrink process, create a partition and format with NTFS. [Using disk management] At this point your new partition has been assigned the next available drive letter. I like drive letters in order so I use disk management to reassign the drive letters for the optical drives so I can assign drive letters sequentially for the hard disk partitions. With the new partition now labeled D and optical drives following, it is now time to install our older operating system.
Boot with your win2k/xp CD [CD set as first boot device in the bios] Select the “D” partition as to where you will install. I will not go into detailed instructions as to how to install win2k or xp; there are many guides on the web for this purpose. Complete the install. At this point, vista will no longer boot; we need to repair the boot sector and vista’s boot configuration files. Boot into win2k/xp and open a command prompt; start>run>cmd and hit enter. We will now use Bootsect.exe to restore the Vista MBR and the boot code that transfers control to the Windows Boot mgr app.
Insert your vista dvd into the drive; cancel window that may autorun. Type this in
Drive:\boot\Bootsect.exe /NT60 All hit enter
In this command drive is the drive where the Vista install DVD is located.
Next we will use Bcdedit.exe to manually create an entry for win2k/xp
Type Drive:\windows\system32\Bcdedit /create {ntldr} –d “Description for earlier Windows” hit enter.
Note in this command drive is where you have vista installed; most likely “C” The description can be whatever you want ie Windows 2000, Windows XP, etc.
We now will set the active partition. Note in this command drive is the letter for the active partition; again most likely “C”
Drive:\Windows\system32\Bcdedit /set {ntldr} device partition=X: hit enter Again this is most likely C not X.
Drive:\windows\system32\Bcdedit /set {ntldr} path \ntldr hit enter
Drive:\windows\system32\Bcdedit /displayorder {ntldr} –addlast hit enter.
Now restart the system and you will have the vista boot menu giving you the choice of operating systems.
Source : Techguy
26-09-2008
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