I've seen many other postings about this, but the answer is always to enable SSO on a single listener for both URLs in TMG. That doesn't seem to be working for me. I have a legacy 2003 OWA server and new 2010 CAS server. They are both published through TMG. Both on the same listener. But I still always have to enter my password twice. They are on 2 separate firewall rules, which from my understanding is correct as each one can only point to a single internal server, but maybe my understanding of that is not correct. On the SSO tab in TMG, I have Enable Single Signon Checked and my root domain listed in the box. Anyone have any other ideas where to look? Thanks! Brian

Hi Brian, Please see my article on configuring 2003 & 2010 with ISA 2006, this will apply to TMG as well. http://ilantz.wordpress.com/2010/03/12/how-to-publish-exchange-2003-and-exchange-2010-with-isa-2006/ Best Regards, Ilantz

Thanks for the reply. I have followed these instructions already when I did my config. I still have the problem. Regards, Brian

Hi Brian, Have you disabled Forms authentication on both 2010 and 2003 ?

Yes, forms based authentication is disabled on both 2010 and 2003 and left on on TMG. I found the problem. On the Single Sign On page in TMG, it asked for a domain. I thought it meant our AD domain because I was thinking it needed that to append to the username to be able to use it. My mistake. Our internal and external domains are not the same and it was asking for the external domain. When I canged that, it fixed the problem.

HI Brian, I am also facing same issue. Can you please explain how u have configure TMG 2010 means you have configured 1 single rule and you are accessing Exchange 2003 mailboxes for Exchange 2010. Regards, Nitin Dongre Regards, Nitin Dongre

Hi Nitin, To publish with TMG 2010 both 2010 and 2003 mailboxes you can follow my guide, http://ilantz.wordpress.com/2010/03/12/how-to-publish-exchange-2003-and-exchange-2010-with-isa-2006/ The wizard in TMG includes the directories for 2010 like /ecp , make sure you follow the article and you will be just fine :) ilantz