Windows Vista tricked into 'upgrading' itself

Researchers have found a way to trick Windows Vista into ?upgrading itself?, potentially saving users the cost of buying a new install version of the operating system. On Friday, Microsoft confirmed reports circulating on the Internet since the beginning of the month that customers can successfully install an upgrade version of Vista on a computer without Windows XP or 2000 already on it, through a bit of installation ledgerdemain.

Here's how the "clean install" trick works according to ars technica:

--Boot with the Windows Vista upgrade DVD and begin the full installation process.
--Do not enter the product key when prompted, but continue on.
--Choose to do a clean install Vista, that is, fully wiping your hard drive.
--After you're done, boot into the still-unactivated copy of Vista.
--Run Windows Vista setup again, from inside Vista.
--Select upgrade, and enter your upgrade key.
--Install Vista a second time.