Dont know if this will help in your environment - I just resolved a
similar situation. I purchased a Dell notebook with Vista installed
recently and experienced problems with Office (Word) documents opening
read-only. The following links helped me resolve it:
This MS knowledge base article describes a different error with
identical error messages:
http://support.microsoft.com/kb/814112
but this one mentioned permission issues with Vista:
http://www.tomshardware.com/forum/235586-44-office-2007-vista-read-only-problem
I had copied files from my old machine to an extended partition on the
new machine (a "D" drive) while logged in as a true administrator on
the machine (I did this because I couldn't figure out how to connect
to the vista machine while logged in as a "regular" admin). When I
logged on to the machine with my regular Vista account I found that
all the Word documents would open read-only, even though no
permissions were set on those documents or on the drive. After
reviewing the above links I logged on as the administrator again and
explicitly added the "regular" admin user to the list of users with
full control on the drive. After that I had no problem.
I've been trying to get used to all the Vista permission issues, but
I'm about to give up and just use the true administrator account. I'm
spending too much time figuring out these kinds of problems...