"Luc" wrote in message
...
Thanks for the information.
Is there a difference between logging in as administrator and running a
program, and right-clicking and run as administrator ?

Yes there is a difference. The Run as Administrator only last for the moment
of privileged escalation, and the user admin is returned to a Standard user.

The link explains the situation when the built-in Administrator account has
the full admin rights power as opposed to your user/admin out of the box
that doesn't have full rights, even a new one you might create.

http://chrisbensen.blogspot.com/2007/02/com-registration-under-microsoft.html


Otherwise, i do not believe this has something to do with my problem...
In normal circumstances you will be logged on as a user, not as an
(full)administrator, and that user should be able to do his
Windows-updates,
isn't it ?

I don't think you can install anything on Vista unless you're Admin or a
Power-user. Power-user is there for backwards compatibilty.


It's clear that i'm not the only one with this problem, but i cannot find
a
solution.

Who has the key ?

Now, if you do the *scan* like I finally got another poster to do in
Vista.General after repeated attempts to get the OP to do the scan in the
link as he couldn't do Windows Updates either, you might find that your
system has corrupted system files.

http://support.microsoft.com/kb/929833

To view the log, you might have to disable UAC, because of the access denied
that you wouldn't get by using the Administrator account, even with UAC
enabled.