You can do a clean install of Vista 64 using an Upgrade key into a
partition containing Vista 32 and when you do the Vista 64 OS totally
replaces the Vista 32 OS.
It does, however, create a folder on the Vista 64 bit desktop called
Windows.Old from which you can copy out data files that may have failed to
back up and then you can delete the Windows.Old folder.
I would imagine that you could do the reverse when you want to Upgrade Vista
64 with a clean install of Vista 32. It is at least worth a try.
"Malke" <malke@invalid.invalid> wrote in message
news:OCC85JuCKHA.5780@TK2MSFTNGP03.phx.gbl...
> craigg1 wrote:
> in
>>
>> I just purchased a desktop computer for my work. It came with Vista Home
>> Premium 64bit. I also purchased the Upgrade to Vista Ultimate since the
>> ultimate version works better with our network. Some of the software
>> that we run at work is not compatible with 64bit so I was wondering if
>> anyones know if:
>>
>> 1. I can install 32bit Ultimate upgrade over 64bit Home Premium ...or
>> 2. If I can use the 32bit Ultimate Upgrade and do a Complete re-install
>> and install Ultimate 32bit
>
> 1. You cannot install a 32-bit operating system over a 64-bit operating
> system. You must do a clean install.
>
> 2. An upgrade version presupposes you are upgrading *from* something,
> which
> you are not since there is no upgrade path from Vista 64-bit to Vista
> 32-bit. Return the 32-bit upgrade and purchase a full version Vista
> 32-bit.
>
> Malke
> --
> MS-MVP
> Elephant Boy Computers - Don't Panic!
> http://www.elephantboycomputers.com/#FAQ
>