We've created a linked mailbox, in Exchange 2013 (in domain1), for a user in another AD forest, domain2. We have the AutoDiscover service configured in the other AD forest as well. Our only issue now is trying to find a way to get the Outlook Auto Account Setup to automagically configure a user's profile the first time Outlook 2013 is started. If we type in the user's email address and name and click Next, the profile is created successfully.
I spoke to Microsoft support who helped me confirm that AutoDiscovery was configured correctly in the other forest. Reading this information (https://technet.microsoft.com/en-us/library/bb124251.aspx ) on AutoDiscover, I found what may be the issue. It notes that
"If the Outlook client is joined to a domain, the user's domain account is used."
Since the linked mailbox is associated with domain1, Outlook looks like it cannot use the domain account from domain2. I wonder if there might be a registry hack to bypass this and force Outlook clients in domain2 to look at email addresses in domain1?
Orange County District Attorney