You are confusing Upgrading with a Clean install from an Upgrade
version. Please read the following quote from:

http://www.winsupersite.com/reviews/winvista_03.asp

Understanding your installation choices
How you acquire Windows Vista play a large part in any decision about
how you will actually install the operating system. At a high level, you
have the following basic choices:

Clean install. With this method, you boot the PC from the Windows Vista
install DVD, run interactive Setup, format the PC's hard drive, and
install Windows Vista as the only OS. This is probably the rarest way to
get Vista on a PC. You can use a "Full" or "Upgrade" retail version of
Windows Vista to perform a clean install, though you will need
"qualifying media"--typically a Windows XP or 2000 CD that proves you
qualify for the Upgrade version.

Upgrade. Here, you insert the install DVD from a "Full" or "Upgrade"
retail version of Windows Vista while running Windows XP and perform
what's called an in-place upgrade. The Setup process is similar to that
of a clean install, but most of your existing applications and all of
your data files will be available and working properly once the upgrade
is complete. Unfortunately, there are a number of qualifications to the
upgrade process in Windows Vista. First, you can only upgrade certain
versions of Windows XP to certain versions of Windows Vista. Here's a
chart that explains which XP versions can be upgraded:




DandyDon wrote:

> Another thing to consider: The Vista Upgrade only installs from Windows, so
> anytime you need a complete reinstall of Vista, you must first reinstall XP.
> No more 'sticking the XP disc in for verification' before install as before.
> So, keep your XP media. If OEM, get a copy of XP from your system
> manufacturer if you don't have 'restore' disks with OEM XP on it.
>
> Otherwise, you will be stuck. Your hard drive copy of XP will be gone, with
> no way to restore it and Vista won't install by itself.
>
> IMO, your best option is to buy the retail version. It can be installed on
> an empty disk.
> "titus12" <titus12@msn.com> wrote in message
> news:ugfH5wlPHHA.4376@TK2MSFTNGP02.phx.gbl...
>
>>Will it be better to install Vista over WinXP Home or do a clean Install?
>>Will Zone Labs have an update ready when Vista goes on sale?
>>
>>Thank you;
>>David
>>
>
>
>