At Least One Exchange 2010 CAS Server Must Be Present

[This topic is intended to address a specific issue called out by the Exchange Server Analyzer Tool. You should apply it only to systems that have had the Exchange Server Analyzer Tool run against them and are experiencing that specific issue. The Exchange Server Analyzer Tool, available as a free download, remotely collects configuration data from each server in the topology and automatically analyzes the data. The resulting report details important configuration issues, potential problems, and nondefault product settings. By following these recommendations, you can achieve better performance, scalability, reliability, and uptime. For more information about the tool or to download the latest versions, see "Microsoft Exchange Analyzers" at https://go.microsoft.com/fwlink/?linkid=34707.]  

Topic Last Modified: 2010-09-21

The Microsoft® Exchange Server Best Practices Analyzer Tool examines each Active Directory® directory service site to verify the following:

  • If the site contains servers that are running Microsoft Exchange Server 2010, at least one Exchange 2010 server must be running the Client Access (CAS) server role.

  • If any site contains Exchange 2010 servers, at least one Exchange 2010 CAS server in the environment must be an Internet-facing server.

To perform this analysis, the Best Practices Analyzer performs the following operations:

  • It enumerates the Exchange 2010 mailbox servers.

  • It enumerates the Exchange 2007 CAS servers.

  • For each Exchange 2007 CAS server, the tool examines the ExternalURL values for the following virtual directories:

    • Autodiscover

    • EWS

    • Owa

    • OAB

    • UnifiedMessaging

    • Microsoft-Server-ActiveSync

  • It enumerates the Exchange 2010 CAS servers.

  • For each Exchange 2010 CAS server, the tool examines the ExternalURL values for the following virtual directories:

    • Autodiscover

    • EWS

    • Owa

    • OAB

    • UnifiedMessaging

    • Microsoft-Server-ActiveSync

If the Best Practices Analyzer cannot find an Exchange 2010 CAS server, a warning message is generated. To resolve this issue, verify that at least one Exchange 2010 CAS server is available.

To view the ExternalURL value for a virtual directory

  1. Start the Exchange Management Console.

  2. Expand Server Configuration, and then click Client Access.

  3. Click the Exchange 2010 CAS server, and then click the tab that corresponds to the virtual directory that you want to configure. For example, click Outlook Web App.

  4. Right-click the virtual directory, and then click Properties.

  5. On the General tab, verify the address that appears in the External URL box. For example, verify an address such as https://mail.contoso.com/owa.

For More Information

For more information about how to configure Exchange 2010 for external client access, see Microsoft Knowledge Base article 982907, Configuring Exchange Server 2010 Client Access Features for Remote Access.