Vista - Upgrade Install from Ultimate?

I am using Vista Ultimate x64 Build 6001 SP1.
Intel® Core(TM)2 CPU 6700 @ 2.66GHz 2.66 GHz Memory (RAM) 4.00 GB, 1 year old
The computer exposes a number of strange symptoms. After an extensive research (including anti-malware scanning) I came to the conclusion that one or more Vista System files are corrupted or missing.
How can I repair Vista without having to reinstall al programs and settings?
Is it possible to trick Vista to make an Upgrade Install (which I understand keeps the programs and settings) from Ultimate to Ultimate? When I try this, a message tells me that I can upgrade only to a newer (?) version.

Thanks a lot,
Dan

You do not have to trick Vista. An in-place-upgrade is supported provided
you have a standard Vista dvd and not a restore or other kind of medium. As
Rick points out, the installed files and the dvd have to be at the same
service pack level. An in-place-upgrade will not disturb your apps.
However, make a system backup just in case. If you are using a laptop you
must be on AC to perform an in-place-upgrade. Try Rick's system file
checker advice first.

"DanA" <guest@xxxxxx-email.com> wrote in message
news:732946b11c0fd0485c9589daaa893c63@xxxxxx-gateway.com...

DanA - boot from the Vista DVD - select setup - files will load - (be
patient) proceed to setup screen which will have an option to repair.
Select repair and and select repair from the tools option,

Vista will scan for a Vista installation - select it for repair. Vistas
(and XPs repair other than Recovery Console) are actually upgrade
installations.


"DanA" <guest@xxxxxx-email.com> wrote in message
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