restricting owa access

[RonG.]

I need to restrict access to owa for my users.
I can't believe that the only way to do it is to
peddle through the menus for each user! has someone
devised a way to use group policy for this?

or possibly assigning/restricting permissions somewhere?
with the need to remove owa access from about 300+ users
I'm looking for a decent solution.

can anyone shed some light on this?

thanks.

-Ron