outlook web access and public folders

[AP]

Is there a way to password lock the public folder for outside viewing.

I like to empose a restriction using a logon credential or even access is
denied page to the http://webmail.mycompany.com/public folder.

http://webmail.mycompany.com/exchange works fine as logon box will appear.

What can be done to restrict the public folder from the outside world from
viewing the public folder?

Thanks so much for any advice.

 

[AP]

Have solved this by setting directory permission using only authenticed
users to the DOMAIN.
Problem I am having now is, OWA works outside the world fine, but inside the
LAN the authentication does not work.
user/pass login does not work.
Have a dns host entry in our dns servers for internal usage.
just stuck with OWA not authenticating user logins from inside LAN.