Outlook via the internet problems

[Udo]

Hi,
we try to configure one laptop to use outlook via the internet. The
description how to do so is very clear and easy, but on one computer in the
outlook profile Email accounts - Microsoft exchange server - more settings -
Connection tab, it says to check the "Exchange over the interbnet" box. But
this box is not there.....

We updated to the latest version, cross checked with the other computers, we
also checked that all Office professional components are installed. All this
is done, but the check box ist still not there.

Please help urgently..

Thanks