This guide is for Exchange 2007 with ISA 2006. Go here for the BIS ISA Exchange 2003 solution.
Ok firstly this guide assumes you know how to configure and publish secure websites through ISA. If you do not know how to do this then read up on it. Until you are confident you can set up and publish websites through ISA using web listeners there is not point continuing.
This guide also assumes the ISA and Exchange servers are both in the same domain. If they are not there are additional steps you must take (explained at the end of the guide).
The first thing we need to do is enable Forms Based Authentication (from now on called FBA) at the ISA box and disable FBA at the Exchange level (if enabled). Read More →