new user forced to reinstall office 2000

I'm running a small network with Win2K on clients and
server, and using Office 2000 applications. My problem is
that if a user logs on to a PC they haven't used before
they get a message saying Office can't be used unless they
install it ("the application must be installed to run").
Office has already been installed on all the PCs, however,
so there shouldn't be a problem.

I found an earlier message from someone else who had had a
similar problem. It was suggested they could solve it by
uninstalling Office and then reinstalling it and choosing
custom install and "run all from my computer". I tried
that but it didn't make any difference.

We are using roaming profiles, which at first I thought
might be the problem, but i can't see anything wrong there
and I'm sure it's something to do with Office setup. Can
anyone help please?

Answered in win2000.setup.