Good day, I am deploying Exchange 2010 in Exchange 2003 environment. having multiple sites one forest/one domain design & have started deployment on one of the sites (Site A). Mailbox server of one of the sites (Site B) resides outbound & does not belong to our Active Directory boundary , users connect to it via HTTPS , note that they do not have any Exchange server in their LAN. When Started deploying Exchange 2010 in site A , users (outlook 2007 client) at Site B are prompted repeatedly for credentials of the new Exchange 2010. note that when cancelling this message it connects successfully . but it keeps prompting for the message. My question is how to get rid of this message. Regards Elias Dayeh

Hello Go to Control Panel Mail Select Email Accounts Select account Click Change More Settings Security Always prompt for logon credentials uncheck that option try this and restart the outlook.Thanks Mouzzam Hussain Visit to my Blog mouzzamh.wordpress.com

That will be autodiscover. How far down the implementation path have you gone? The authentication prompt can also be generated by an SSL certificate issue. If the clients do not trust the SSL certificate (because you haven't implemented a commercial SSL certificate) then an authentication prompt can be generated. Autodiscover runs in Outlook 2007 by default. The autodiscover information is published to the domain automatically and the clients will pick it up. Even on Exchange 2003 Outlook 2007 was attempting to do autodiscover in the background. The first thing you should do is implement a commercial SSL certificate on to the server. That should stop the authentication prompts. Simon. Simon Butler, Exchange MVP Blog | Exchange Resources | In the UK? Hire Me.

Hello, This issue should be related to your certificate. You should make sure if the certificate is created by a CA trusted by the client computer's operating system and check if the certificate name is correct. Besides, please check if you select Ignore for Client certificate on autodiscover virtual directory. Best Regards, Lisa

Dear All , Actually at the first of installing Exchange 2010 in site A ,the certificate prompt was appearing to the users in the site B , now it is not appearing anymore, but the user login window is appearing . Sembee, I am applying certificate but it is local CA , & it is working fine , am I still have to apply a commercial one ? Lisa, the autodiscover virtual directory is configured to Require SSL & ignore Client certificate. is there a way to disable autodiscover feature on the clients in site B as a workaround ? Regards Elias

Take off the require SSL, that isn't required if you set that. If you are exposing the server to the internet and allowing OWA from any computer outside of your control, then you should use a commercial SSL certificate. Internal CA SSL certificates can only be used when you have control over 100% of clients connecting to Exchange, by any means. Simon. Simon Butler, Exchange MVP Blog | Exchange Resources | In the UK? Hire Me.