You cannot connect to a clustered Exchange 2007 server through a server that has the Client Access Server (CAS) role installed by using the /exchange virtual directory

Your mailbox is located on a server that is running Microsoft Exchange Server 2007. You use Windows Internet Explorer to try to connect to Microsoft Office Outlook Web Access against a server that has the Client Access Server (CAS) role installed by using the <server url>/exchange URL. However, you receive the following error message: The connection is successful if you connect to Outlook Web Access by using the /owa virtual directory.

If you try to connect by using Microsoft Entourage 2004 or a later version of Microsoft Entourage, the operation is unsuccessful. Additionally, you receive the following error message:

This problem occurs because the CN=HTTP container under CN=Protocols is missing for the server object. Therefore, Legacy virtual directories such as /exchange, /exadmin, and /public are missing in Internet Information Services (IIS).

To resolve this problem, follow these steps:

1. Click Start, click Run, type adsiedit.msc, and then click OK.
2. Expand CN=Configuration, expand CN=Microsoft Exchange, expand CN=<OrganizationName>, expand CN=Administrative Groups, expand CN= Exchange Administrative Group, expand CN= Servers, and then expand CN=<ServerName>.
3. Right-click CN=Protocols, click New, and then click Object.
4. In the list, click msExchProtocolCfgHTTPContainer.
5. Click Next, and then type HTTP in the Value box.
6. On the affected Exchange 2007 server, start Exchange Management Shell.
   
   Note This operation must occur on the affected mailbox server.
7. Run the following cmdlet to create the virtual directory in IIS and in Active Directory:
   New-Owavirtualdirectory -owaversion:exchange2003or2000 -virtualdirectorytype mailboxes -name exchange
8. Use the new-owavirtualdirectory cmdlet to re-create the public virtual directory and the exadmin virtual directory.

Note The ADSI Edit tool is included in Microsoft Windows 2000 Support Tools and in Windows Server 2003 Support Tools.

In IIS Manager for the Web site on the server, you will notice that some or all legacy virtual directories are missing. By default, these are configured at setup and must be present for Entourage and WebDAV to connect.

If you try to re-create the virtual directories by using the new-owavirtualdirectory cmdlet, you receive the following error message:In a clustered Exchange 2007 environment, all nodes of the cluster should have these Active Directory objects and IIS virtual directories.

On a server that has the CAS role installed, you may have to re-create the exadmin virtual directory. However, the server that has the CAS role installed does not use the exadmin virtual directory. For more information about how to re-create Exchange Server virtual directories, click the following article number to view the article in the Microsoft Knowledge Base: