having issues with autodiscover in this scenario Client machines running Outlook 2010 are joined to Domain B User accounts are in Domain A Exchange 2007 is in Domain A There is no Exchange org in Domain B (schema never prepared for any version) Domain A and B are separate forests, but have trusts. DNS is shared. Neither A nor B use the same namespace as our internet domain (i.e. not the same domain as what's in everyone's SMTP) Autodiscover in Outlook fails. It's able to determine the user's SMTP but then it tries accessing the https://internetdomain.com/autodiscover URLs which are not in place. How to make Outlook running from a computer in Domain B, with a user account in Domain A find the Exchange servers in Domain A? I guess it comes down to, does autodiscover use the computer's domain or the user's?

To answer your specific question, autodiscover will pull information from the same domain that the user is currently logged in to. As that domain doesn't have Exchange, it will fail. Therefore you will have to treat those users as external users. The trust is for authentication only, nothing else. That means either you need to configure Outlook Anywhere and all of its URLs so that they resolve, or the internal URLs also need to resolve correctly for those users to the internal users. If there is no firewall in place, then the second option will be fine, if the traffic is restricted, use the first option as it only requires port 443. Simon.Simon Butler, Exchange MVP Blog | Exchange Resources

Thanks. The user's credentials are in the same domain as Exchange but their computers aren't. I'll look at Outlook Anywhere internal url's as this is all behind the same firewall. I'm also thinking of putting a CAS server in the domain B - think it would help with some way to provide autodiscover settings that point back to the Domain A? Connectivity works perfectly but I'm trying to stay away from manually created profiles. Mailbox access is easy enough but without autodiscover, getting the availability service to work is a hassle.

A CAS server in the second domain is going to be useless, and will actually stop things from working completely. If you aren't deploying mailboxes in that domain then don't deploy any part of Exchange. This has to come down to name resolution. The clients needs to be able to poll autodiscover.example.com (where example.com is their email domain after the @ sign), and then the resulting URLs needs to resolve correctly for them to the relevant IP addresses. That is it. Nothing else is required. You just need to sort out the DNS. Simon.Simon Butler, Exchange MVP Blog | Exchange Resources

please reffer to "How to Configure the Autodiscover Service When You Use Multiple Forests " section in the white paper below http://technet.microsoft.com/en-us/library/bb332063(EXCHG.80).aspx Dhruv

Thanks, I saw that article before but I think I missed the point of it. Looking again, I think creating the SCP in the other forest and export-autodiscoverconfig might do it. I should have mentioned we do plan on moving Exchange to that forest at some later date so I'll be building CAS servers in there. Getting autodiscover.example.com (or anything Windows-related on that domain) to resolve opens some technical and non-technical issues in our environment but would work too. Thanks