I am in the process of removing the first exchange 2007 server in a mixed environment. We have a client access server running exchange 2007 on server 2008, the first exchange 2007 server running Hub Transport, Client Access and Mailbox on server 2003, and another exchange 2007 server running Hub Transport and Mailbox roles. The exchange 2003 running server 2003 is only doing relaying. I removed the client access service on the first exchange 2007 server and now getting an Authentication popup box on the outlook 2007 clients. Once it started happening I reinstalled the client access back onto the server, but still have the same problem. OWA and all of the smart phones still work. It looks like auto discovery for external is working, but not for internal.

have you tried to recreate outlook profile for affected user???

Please check internal URL of first exchange 2007 server where you have reinstalled CAs role. What is error you are getting when checking autodiscover from MAPI clients like outlook. Anil

hello Anil, i dont think that there will be any issues with Autodiscover URL, as outlook is able to connect to exchange server, we need to check for the server name in Authentication popup box .Rregard, Prem Desai

What exactly the error message you are getting?Gulab | MCTS-MCITP Messaging: 2010 | MCTS-MCITP Messaging: 2007 | MCC 2011 | Skype: Gulab.Mallah

The server is owa which is only running the client access role and has a single certificate from geocert. I changed our internal DNS to the external IP and now I am not getting the popup, but we cannot access OWA from inside the network due to firewall. Outside stuff is still working fine.

Again what is the error you are getting when trying to access OWA?Gulab | MCTS-MCITP Messaging: 2010 | MCTS-MCITP Messaging: 2007 | MCC 2011 | Skype: Gulab.Mallah

internet explorer cannot display the webpage When I click on the diagnose connection problems I get Your computer appears to be correctly configured, but the device or resource (server.Domainname.com) is not responding.

How’s the issue currently? The environment is: Server 1: Exchange 2007 CAS Server 2: Exchange 2007 CAS, MBX, HT Server 3: Exchange 2007 MBX, HT Server 4: Exchange 2003 Quote: “The server is owa which is only running the client access role and has a single certificate from geocert. I changed our internal DNS to the external IP” Does the authentication popup related to certificate, like name mismatch? Please use the references below for troubleshooting Security warning when you start Outlook 2007 and then connect to a mailbox that is hosted on a server that is running Exchange Server 2007 or Exchange Server 2010: "The name of the security certificate is invalid or does not match the name of the site" Outlook 2007 and Exchange 2007 Certificate issue James Luo TechNet Subscriber Support in forum If you have any feedback on our support, please contact tngfb@microsoft.com Please remember to click Mark as Answer on the post that helps you, and to click Unmark as Answer if a marked post does not actually answer your question. This can be beneficial to other community members reading the thread.