A post in the GBM Forums from Benjamin Ries sheds some light on the recent brouhaha over Vista Upgrades and possible restrictions. I’m copying the majority of Benjamin’s post here:
There have been posts across many sites regarding Microsoft’s policy vis-a-vis new restrictions on installation options for Vista Upgrade licenses.
Fact: If you purchase a Vista Upgrade license (cheaper than the standalone version; requires license to previous version of Windows) you will be required to have your old version of Windows installed and running on your PC at the time of the Vista upgrade. This is different than past upgrade procedures, where you could start with a blank drive and only be required to insert a CD copy of your previous Windows version before proceeding with the new installation.
Why? Because with Windows Activation (introduced with XP), proving ownership of a prior Windows license requires much more than the physical disk, which anybody can download and burn these days. Last time around, a Windows 95/98/2000 disk and CD-KEY were literally as good as a working installation in terms of establishing license ownership.
Fact: A “clean install” is generally better than an “upgrade install” – greater stability, no inherited bugs or files from last OS, etc.
Myth: That an “upgrade install” is your only option when you buy a Vista Upgrade license.
Why? Because on any Vista disk – whether a standalone or upgrade license – the install procedure will give you two options: (a) install Vista “on top” of the existing OS, or (b) clear existing files and THEN do a “clean install” of Vista.
The only difference, as far as I can tell, is that Vista requires you to begin with your old OS installed (and if XP, activated) before you start the Vista install. Once it verifies your existing Windows license, you can decide how the installation should proceed (upgrade or clean install). In fact, if your old OS is older than XP or the SKU doesn’t match up, clean install is your only option! (https://arstechnica.com/news.ars/post/20060730-7384.html)
So yes, this is a minor pain in that you can’t begin with a blank hard drive. But no, you don’t have to do an “upgrade install” of Vista. The installation menu always provides “clean install” as an option. So there’s no real need to go through an XP install first unless you’ve got a brand new hard drive – you can start from your currently bugged up, fundamentally flawed XP partition and end up with a “clean install” of Vista.
Thanks for the info Benjamin.