Hi, EdC.
There two right answers to your question.
1. Yes, the EULA allows you to install the x64 version to replace your x86
version. The retail Vista Ultimate package comes with two DVD-ROMs, one for
32-bit and the other for 64-bit - along with a single Product Key. You can
use that single key to activate either version - but only one at a time can
be installed. OEM versions of Vista that come pre-installed on a new
computer usually can't be swapped except by negotiating with the hardware
vendor.
2. No, you can't "upgrade" ANY 32-bit OS to ANY 64-bit OS - or vice versa.
You'll have to use the "custom install", which basically means to reformat
the volume where you plan to install the new version. So, back up all your
data first, and be sure you have media to reinstall all your applications.
RC
--
R. C. White, CPA
San Marcos, TX
(e-mail address removed)
Microsoft Windows MVP
(Running Windows Live Mail 2008 in Vista Ultimate x64)
