can not access to "c:\documents and settings\all users\documents"

[Yu]

I have such a problem, when I install a new software, it
told me that i can't access to "c:\documents and
settings\all users\documents". In fact, I log on using an
adminstrator account, I don't know why I still can not
access to it. I tried to browse that "documents" folder ,
but it said "c:\documents and settings\all
users\documents is not accessiable". I am using Windows
XP home edition.
anybody knows what happened?
thanks