Hi We have an exchange front end server 2003 and when the user is authenticate by AD OWA lets the user straight into there mailbox with out re-authenticating Now we have put in a CAS server exchange 2007. Windows 2008 64 bit and IIS 7.0 now when the user access the exchange virtual directory it is asking the user to re-authenticate which we do not want The mailboxes are still on Exchange 2003 I pressume this is a permisions problem on the virtual directory but have played around with them and it has made not difference Can anyone advise thanks

Here is a matrix of all the scenarios: http://msexchangeteam.com/archive/2007/02/07/434523.aspx or http://technet.microsoft.com/en-us/library/bb885041(EXCHG.80).aspx Outlook Web Access and Exchange 2007, 2003 and 2000 coexistence Is this yours? You deploy one Exchange 2007 computer that has only the Client Access server role installed. You deploy one Exchange 2007 computer that has only the Mailbox server role installed. You deploy one Exchange 2003 back-end server. You have mailboxes on both Exchange 2007 and Exchange 2003 servers. If the mailbox is located on an Exchange 2007 server: Requests to /owa return the Exchange 2007 Outlook Web Access experience. Requests to /exchange on the Client Access server or Mailbox server redirect the user to /owa. Authentication credentials are passed through transparently. Requests to /exchange on the back-end server direct the user to the Client Access server. However, the user may have to be authenticated again. Requests to /public are directed to /public on the back-end server. Requests to /exchweb are directed to the back-end server or do not return anything. If the mailbox is located on an Exchange 2003 server: Requests to /owa return the error message shown in Scenario 2. Requests to /exchange or /public on a Client Access server are proxied by the Exprox.dll to /exchange or /public on the back-end server and provide the Exchange 2003 Outlook Web Access experience. Requests to /exchange or /public on the back-end server provide the Exchange 2003 Outlook Web Access experience. Requests to /exchweb are directed to the back-end server or do not return anything.

Hi This is our setup Example 2 except we have more than on BE server. The thing that i notice is in example 3 if there is an exchange 2007 mail box server it states you may have to log back in again to 2003 back end server I wounder if this is the case with example 2 as well and we can not rectafy this until we upgrade to 2007 Example #2 1 Exchange 2007 CAS-only server 1 Exchange 2003 BE server All mailboxes on the BE server Requests for /owa returns the following error since there are no Exchange 2007 mailboxes. Outlook Web Access could not find a mailbox for DOMAIN\USER. If the problem continues, contact technical support for your organization and tell them the following: The mailbox may be stored on a Microsoft Exchange 2000 or Microsoft Exchange 2003 server, or the Active Directory user account was created recently and has not yet replicated to the Active Directory site where this Client Access server is hosted. Requests for /exchange on the CAS are proxied to /exchange on the BE server, which returns the OWA 2003 experience Requests for /public on the CAS are proxied to /public on the BE server, which returns the OWA 2003 PF experience Requests for /exchweb: exprox either proxies them to /exchange or /public on the Mailbox server, or does nothing with them