UAC problem

This might be an Office 2007 problem, but I think it is a Vista problem.

New build
Vista Ultimate 64 bit
4 GB ram
2.13 GHZ dual core
80 GB HDD, SATA, 40 GB free

On 01 Feb, Vista installed, with user "U N".
[ " U N" is an alias to protect the identity of the innocent. ]
All subsequent action performed with user account "U N".
Office 2007 Standard installed using upgrade & Office 2000 CD for qualifying
product.
All verified & activated.
At this point, Word, Excel & Outlook all worked.
Setup Outlook; transferred old outlook.pst to C:\user\UN\documents\email
Pointed Outlook to said folder.
Life was good. We could read old email, send & receive new email.
As best as I can recall, this was the last time Office 2007 programs were
verified as working.
Norton Internet Security 2007 installed.
We could access the internet.

POP3 is comcast, not MSN as
http://support.microsoft.com/kb/930008/en-us?spid=2520 notes.

On 02 Feb, user tried to install Act 2005, which failed.
Then, the user tried to install [ QuickBooks ] QB 2007, which failed. User
called Intuit. They blamed & referred the user to Microsoft.
I uninstalled QB.
I installed the Windows Cleanup Utility [ which is 64 bit & Vista compatible
] & used it.
Then, I installed QB 2007 using the Program compatibility feature, with a
setting of compatibility to Windows XP.
QB 2007 works well.

Open Outlook, Excel, Word and Windows tells us that the program has not been
installed for the current user. This is the only user, except for
"Administrator" on the computer.

I searched the internet & found references to "User Access Control". But the
most recent reference was Dec 2006 & RFC. I found no references to the
commercial Vista.

I turned off UAC, rebooted & viola, Office 2007 programs worked fine.
I turned on UAC, rebooted, Office 2007 programs did not work fine.

I repaired Office 2007 using the "change" feature in "programs & features.
Same problem.

I uninstalled Office 2007.
Ran Windows Cleanup Utility, but no references to Office 2007.
With UAC on, I installed Office 2007. Same problem.

I uninstalled Office 2007.
Ran Windows Cleanup Utility, but no references to Office 2007.
With UAC off, I installed Office 2007. Same problem.

I tried to install Office 2007 in safe mode, but the Windows installer would
not run.

With UAC off, when I opened Word, I received a message that "Word failed to
start correctly last time. Starting word in safe mode will help you correct
or isolate a staratup problem in order to successfully start the program.
Some functionality may be disabled in this mode. Do you want start Word in
safe mode?"
I selected "no".
I started word: winword /a
Life was good.

I turned on UAC, rebooted. Opened Office 2007 programs & the program has not
been installed for the current user.

Re-install, repair re-install & sfc /scannow , have been considered. I will
try sfc /scannow first.

I hope you can offer additional suggestions.

wc