By Michael Santo
Executive Editor, RealTechNews
Microsoft is ending their past policy with regards to upgrade installs, starting with Windows Vista. In the past, for example, you could perform a clean install of Windows XP Professional using an upgrade CD, by doing the normal install, then popping in a Windows 98 or Windows 2000 CD when prompted. Then the install would continue. For Vista, this will no longer suffice to satisfy the bean counters at Microsoft.
Microsoft has cut out this process for Windows Vista and forces users who buy an upgrade CD to actually have a valid install of Windows XP Home or Professional on their machines before upgrading. For most users, this wouldn’t be a problem. They more than likely have an existing copy of Windows XP installed and would have no problems upgrading to Windows Vista with an upgrade CD.
But for do-it-yourselfers who buy a Vista upgrade CD and think that they can easily perform a clean install whenever they feel free are going to run into the road block. Source: DailyTech
We Say: Many may say, what’s wrong with that? But when switching OSes like this, you should really have a clean install. Otherwise you’re going to have a system full of unused files and garbage. I realize that most users will just go with the direct upgrade, without starting from scratch, but I wouldn’t be one of them.
Finally, let’s not forget how much fun you’ll have if for some reason your hard drive crashes. Install XP, then install Vista. Fun! 
It appears that this may only apply to Home versions and not to Business or Ultimate: http://support.microsoft.com/kb/930985/en-us
I’ll upgrade when my machine gets tired of spinning it’s wheels.
This wont last long…
When customers want to upgrade their hard drives or have crash…
Many customers that had the OS installed initially wont have their previous version of windows install. So then what?
FedEx install CD from Microsoft…
BeDammit
Nonsense. Some upgrade scenarios *require* a clean install. http://www.microsoft.com/windows/products/windowsvista/buyorupgrade/upgradepaths.mspx
PC Perspective is also saying that the XP install can’t just be any XP install. It has to be a SP2 XP install.
Just give me 1 good reason why you would want to upgrade to Vista. Do you enjoy pain and suffering? Just buy that new computer or hardware next year with Vista SP2 and save yourself some headaches.
The funny thing is that with Vista there technically no such thing as an ‘Upgrade’. When you run Upgrade, it does a clean install of Vista and then runs it own migration tools to copy your data and settings. So even an upgrade isn’t really an upgrade.
I can get even worse if this policy is kept for the future versions… can you imagine install Xp -> install Win Vista -> install Win Horizon -> install Win Estratosphere –> etc
Great, so lets say you get some Vista only hardware. A new HD that XP will not recognize not even with the F6 press on install to load a driver manually. Guess what? You can no longer user your legal copy of Vista either.
Plus who wants the old XP stuff laying around? Good thing I did the work to slipstream SP2 onto my XP CD so I could get back to Vista sooner if I ever install it. Looks like that is going to be an even longer time out now.
Workaround found: During 1st install, don’t enter key code. Vista installs as trial version. Install again, using key code. Delete old files. Convoluted, but supposedly it works. Full article at http://www.dailytech.com/article.aspx?newsid=5932
[...] Earlier I wrote about clean installs not being available any longer with Windows Vista Upgrade DVDs. There was conjecture that it might be related to Home versions, but even the mainstream press was confused. Now, it seems Paul Thurott, through some internal Microsoft documents, has discovered a workaround. However, he did not test it, but the enterprising folks at DailyTech did, and they confirm it works. [...]
[...] “Many may say, what’s wrong with that? But when switching OSes like this, you should really have a clean install. Otherwise you’re going to have a system full of unused files and garbage. I realize that most users will just go with the direct upgrade, without starting from scratch, but I wouldn’t be one of them.”–Real Tech News [...]
Two issues are getting intertwined.
a. upgrade versions: yes, you need to install on a computer where XP resides
b. clean install: yes, you can do a clean install — i just did with vista business upgrade.
my strategy:
xp resided on a fat32 volume.
patitioned a new volume on a separate hard drive (in this case third hard drive, H:). and used partition magic to format it was ntfs.
C. then i ran vista setup from within xp.
D. because xp was on a fat32 volume, the install blocked the choice to install there and instead presented only one choice: a full install on H:, the ntfs volume.
E. installed like a charm and validated just fine.
buzzing along.
You can perform a Clean Install of All Versions using just an upgrade disc to see how just click the link and find a post yes you can
http://forums.cnet.com/5208-12546_102-0.html?forumID=133&threadID=226764&messageID=2365399
Whats the damn problem? Either install a pirated copy of XP then install a legit copy of Vista, or install a pirated copy of Vista. Or install Linux. Option three perferred
oh well, more power to the linux gods.