When setting up a client access array, do you need to specify the EXCH provider? For example, Set-OutlookProvider EXCH Outlook.company.com? Our value is currently blank.

I should have been more specific. The CertPrincipalName and Server names are blank. OutlookProviderFlags is set to None.

Hi, Server and CertPrincName only apply to Outlook EXPR provider(outlook anywhere) If the request is made by an Outlook Exchange RPC client, the EXCH provider will return the InternalUrl configured on the best CAS server for the following services: Availability Service, OAB virtual directory and Unified Messaging virtual directory. So please verify if you have correct configured the internal URL for the above services. Related information to share with you: When, if and how do you modify Outlook Providers? http://blogs.technet.com/b/exchange/archive/2008/09/29/3406352.aspx The Autodiscover Service and Outlook Providers - how does this stuff work? http://blogs.technet.com/b/exchange/archive/2008/09/26/3406344.aspx Regards, Xiu