I have a new install of Exchange 2013, with the DC on a separate machine with Server 2012. I'm trying to setup users on it. Machines that have Windows 7 connect completely fine. No interaction is needed to get Outlook up and running. Machines with Windows XP SP3 cannot connect at all. Using Internet Explorer and going to https://mail.domain.com/owa shows a "Internet Explorer cannot display this webpage". Trying to connect with Outlook 2007 shows a "Connection to Microsoft Exchange is unavailable. Outlook must be online or connected to complete this action." error box. Both the DC and Exchange machines are using Centralized Certificates. I have SSL certs for both the mail.domain.com and autodiscover.domain.com installed. I can connect to https://mail.domain.com/owa from Firefox and Chrome on the XP machines and all shows OK. Just not IE. This is the log from Outlook when trying to connect: Autodiscover to https://autodiscover.domain.com/autodiscover/autodiscover.xml starting GetLastError=12030; httpStatus=0. Autodiscover to https://autodiscover.domain.com/autodiscover/autodiscover.xml FAILED (0x800C8203) All tests from TestEchangeConnectivity pass.

It's weird and true that IE will act like that, you have to change the security settings on IE. About the autodiscover, check the proxy settings on IE make sure it's not set to include internal Servers to be accessed via Proxy Server. Check the the Encryption on Outlook and make sure it's enabled.Gulab Prasad, gulab@exchangeranger.com My Blog | Z-Hire Employee Provisioning App

Turns out it was a couple of issues. I did not have an SSL certificate in IIS for the * https binding. But I did have certs applied for autodiscover and mail bindings with centralized certificates. Applying a cert to the * https binding fixed some of the issues. I was also using http redirect and url rewrite to make accessing OWA easier. I disabled both and turned to using an html doc with some javascript to do the same task. This fixed the last of the issues.

Hi Scott, I have exactly the same symptoms on my XP clients with Outlook 2007 and 2010. unfortunately, I'm not very good in the stuff you subscribe; would you mind detailing yuor solution step by step? Much appreciated and best regards! BenVAR Belgium

Dear Scott, The same problem with me. XP clients with Outlook 2007 and 2010 keeps asking for password. Please help us. Thank you.