Thanks John, will check back later. I was searching MS 7 site, but can't find anything regarding this.
That doesn't mean it's not true. But should be out there to inform people. Cause I know I'd be angry after buying Pro/Ultimate Upgrade just to find out that I can't upgrade my XP Home or Vista Basic/Home Premium.
With that said, there are ways around it. And this is not for me personally, but should definitely be known by all.
I don't remember where I saw the explanation we are discussing - may have been in an online magazine article or on a Microsoft Connect blog or - - I forget at the moment. I will find it soon.
Microsoft's position on this is: For instance, If you bought a copy of Windows Vista Home Basic (whether a retail box or preinstalled on a new computer) you paid a certain price for it. You could have used that OS, or for a certain (hefty) additional price, you could have upgraded it to Windows Vista Ultimate, but you chose not to spend the money for the upgrade to Ultimate. Now, since you only paid for Vista Home Basic, that same level is all that you can upgrade to with an UPGRADE installation key. If you wish to move to a higher level when you install Windows 7, you have to pay the same (or equivalent) upgrade price premium that you would have had to pay to make the same level upgrade in Vista. If you buy a Windows 7 Ultimate retail box, you will have paid the premium price and can upgrade any lesser version to that level. You wanna play, you gotta pay! You know Microsoft ain't gonna give nothin' away.