Vista is a proprietary system and it is a feature of the recent MS systems to check integrity of every partition it has to mount. It appears a possibility that Vista will not tolerate seeing another set of identical system files in the PC, especially this new set of system files was not created with its knowledge. Vista then proceeds to make both systems inoperable.

I once had Vista, XP and Linux in a cloned hard disk accidentally hooked with the source disk. The resulting 4 MS systems were sabotaged when I ran Vista. I wasn't sure of the culprit at that time.

It is true that the clone should always run "without" the presence of the source disk. There is no difficulty in cloning a Vista. Just don't let it see another copy of itself in any boot up.

I am in a foreign country and just bought a laptop with a 160Gb disk with nothing but Vista inside. I downloaded Slax and PCLinuxOS from the Internet, bought a couple of CD-RW discs and cloned the Vista into 3 other newly bought portable hard disks.

I am replying with Linux in a backup copy of Vista disk in a 250Gb laptop hard drive. The details of backing up Vista has been described in here.

The Vista in my case has been cloned from an internal 2.5" 160Gb to an external 3.5" 500Gb which could not be verified its success because Vista does not support booting from external disk. However when the image of the 500Gb was transferred to a 2.5" 250Gb laptop disk which was placed into the laptop Vista booted up same as the original activated version. In the above link I explained the reason why I think Linux can successfully clone Vista from a bigger hard disk (500Gb) into a smaller hard disk(250Gb).

At the end of the day if something happens to a proprietary system a user is in a helpless situation if he/she does something outside what the system permits him/her to do. In Linux after even a small bit of the system is understood a user can do amazing things. I think using the "dd" command to clone Vista, which is one of the most difficult systems to clone, falls into this category.