Change Exchange 2010 Autodiscover hostname

http://www.msexchange.org/articles-tutorials/exchange-server-2010/management-administration/exchange-autodiscover-part2.html

On the Exchange CAS server:
Set-WebServicesVirtualDirectory -Identity “mailserverhostname\EWS (default web site)” -InternalURL https://mail.terminalcraft.com/ews/exchange.asmx