So here's my problem. I've got an Exchange 2007, Exchange 2003, and Exchange 2000 server on the network. I've moved all my mailboxes off the Exchange 2000 server to the 2007 sever, moved the roles (routing group master, Recipient Update Services, etc) to the Exchange 2003 server and shut down the services on the 2000 box as we're going to decommssion the box. So far so good with one exception. Users with Oulook 2007 have difficulty setting up an Exchange account. It prompts me for a user name and password (which is shouldn't) when I enter the username and password using domain\user name and password, it continues to prompt me again. If I hit cancel, I get the following error: The connection to Microsoft Exchange is unavailable. Outlook must be online or connected to complete this action. I can ping the exchange server by name, by IP, i've added it to the hosts file, you name is, however it will not resolve my exchange server name or my user name. Curiously enough, Exchange 2003 clients have no problems connecting at all. Any assistance would be appreciated. Thanks, Anthony

Did you find a solution to this? I have the exact same problem. Jim

Have you configured the autodiscovery feature on Exhchange 2007 CAS server?