As you may have heard, Microsoft is cracking the whip on upgraders. If you want to put a Vista upgrade on your computer, you'll need to have a running, older version of Windows there for it to sniff the bottom of. This doesn't sound unreasonable - until you need to reinstall some time in the future. Then, you'll have to dig out your old operating system, install it, then do the Vista install on top.
How much fun is that? Not much. But still just that little bit more fun than you'll have if you've damaged, lost or given away your old XP disks and keys - when you'll be left with a dead computer and no way back to heaven.
We're not going to let that happen. Here's how to bypass Microsoft's compliance check -- and laugh while you're doing it.
First, boot from the Vista upgrade install disk. It'll ask for your key - don't give it. It'll then ask what version you bought - select that. The trial version will now install. Reboot and repeat, this time providing your key and choosing a clean install. Voila - one running copy of Vista from one disk.
Still a pain in the Aero - but at least you get to run the software you paid for.
(Thanks to pal DJ for the info, who got it from here. How broadminded of Mac fans to help solve Bill's little stupidities)