Error message: insufficient privileges to modify this file

I have a brand new (purchased in May) Dell PC with Vista Premium.  Since it
is a family computer, I set up each user (husband, teenaged daughter, and
self) with administrater accounts so we would all have full access.
Nevertheless, we continue to have issues with downloading, installing, or
updating certain software and sometimes with trying to uninstall programs
we've decided to get rid of; we frequently receive the dreaded Error message:
and tried to change the privileges to try to give at least myself full access
to whatever file we're trying to modify, since I am by default the
(self-taught) "techie" for the family.  This sometimes works, sometimes does
not.  The latest most annoying problem in this regard is with I-tunes.  The
version on  the computer, which we tranferred from our old computer, needs
updating, but Vista wouldn't allow it.  I then tried to broaden the access
privileges, and was unsuccessful.  I can't seem to find any way to get Vista
to allow updating on this file.  Does anybody know how to resolve this
problem for I-tunes in particular and for the system overall, since it is a
recurring problem?

Right click on the iTunes.exe file and select "Run as administrator".

Right click on the iTunes.exe file and select "Run as administrator".
--
Paul

Have you tried turning off UAC (user accounts control)?

Have you tried turning off UAC (user accounts control)?

PaulB, I tried this and got a similar error message saying I don't have

PaulB, I tried this and got a similar error message saying I do not have
sufficient privileges to modify the file "itunes.icxs," which I cannot find on
my computer.

I didn't know this was possible. Can you tell me how to do it?

I did not know this was possible.  Can you tell me how to do it?  I will be more
than happy to give that try, we really do not need the this kind of control.

Error message: insufficient privileges to modify this file

I do not recommend leaving UAC turned off, but ...
http://www.howtogeek.com/howto/windows-vista/disable-user-account-control-uac-the-easy-way-on-windows-vista/

-Paul Randall

Unfortunately, turning off the UAC did not resolve my problem concerning

Unfortunately, turning off the UAC did not resolve my problem concerning
privileges to access files.  After I turned off the UAC, I tried updating
ITunes and QuickTime again and received more, similar error messages
concerning first, the Apple updater, then various subfolders in the ITunes
and QuickTime’s folders.  Every time I corrected the privilege issue with one
file, the next try resulted in another error message about another file.

The good news is that after much trial and error (which is the way I've
learned most of what I know about computers, with occasionally tips from
helpful people like you all to send me on the right trail,) I finally
resolved my issue and think what I did will be a fix for any future similar
issues.  In short, I discovered that every single file and subfile you are
trying to access and modify must be both owned by the Administrator and have
all the relevant privileges enabled.  I also discovered that not all subfiles
(at least of a downloaded program) are designated as owned by the
administrator and even if a file is owned by the admin, the privileges are
not necessarily enabled.

At first, I thought I had to go through each and every folder and subfile to
check and change everything manually, but I finally discovered a shortcut
that appears to work (though I'm not going to hold my breath that it will
always do so.)  Right click on the main folder in the Program Files directory
and go to Properties.  Go to the Security tab and click on Advanced, then
Owner to see who owns the file.  If it is not Administrator, click on Other
Users or Groups to change ownership.  Type Administrator into box, click
Check Names, and the name of your Administrator will appear; click OK.  When
you get back to the Owner page, click on name of Administrator until it
appears as name of Current Owner.  NOW, HERE’S THE IMPORTANT PART: at the
lower left is a box that says “Replace owner on subcontainers and objects.”
CHECK THIS BOX!  If you don’t you will have a bunch subfiles that will still
be a problem.

After that, click OK, then OK again and you should be back at the Security
tab.  Click on Edit, highlight the administrator’s name in the box, and click
on Full Control under the Allow column.  Click OK, then OK again, and you
should be done.  Check a couple of subfolders to be sure.  If this doesn’t
work, either you missed a step, I missed step in my directions (I don’t think
I did, but I can’t be sure, there’s a lot of them,) or my theory only worked
on my one problem and is not a universal cure-all.  If anybody tries this on
a similar problem with Vista and another “insufficient privileges” problem,
please let us know how it goes.

Thanks, everybody for your efforts to help me out.  I hope I’ve contributed
something useful.