I'm only using Integrated Windows Authentication for the default Web site and for the virtual server.
Obviously I'd like to make OWA more convenient for my users by only prompting them for their username and password once. Any help would be GREATLY appreciated. Thanks!
Wow, I didn?t think you could have ISA and Proxy running on the same box. ISA is supposed to be an upgrade to Proxy 2.0. In either case, that may or may not be the problem.
There are certain conditions under which Integrated Windows Authentication must exist. First is that you cannot go through a proxy server when using Integrated Authentication. This type of authentication cannot be proxied, so if your users are accessing OWA via a Proxy or ISA, IWA will not work.
Another condition is at the client-side. First, if you are using Netscape, forget about it. Netscape doesn?t support IWA. You must use Internet Explorer for this. And when using IE, you either need to use a NetBIOS-based URL (e.g., http://server/exchange as opposed to http://server.mydomain.com/exchange or http://10.1.1.1/exchange). If you use an FQDN or IP address in the browser, and your browser is configured to use a Proxy, then IE will automatically turn off IWA because it knows IWA cannot be used through a proxy. You will need to exclude the proxy for whatever specific address you are using to get around this problem.
The three prompts are an indication that IWA is failing on you. Once you have configured your environment properly, IWA won?t prompt you at all. It will used your currently logged on credentials and take you right to your mailbox.
Hope this helps.
This was first published in January 2002