I am moving a customer from onsite network to a hosted solution. I need to leave the onsite domain in place and move the Exchange mailboxes to the hosted Exchange server. The old Exchange server will be decommissioned. Both the local and hosted domain name are the same - abcxyz.com. I have RPC/HTTP on the hosted server. I need to authenticate to the hosted Exchange server. When I try to connect to the hosted Exchange server, it will not accept my login. How can I make this work?