Topic Last Modified: 2005-11-18

The Microsoft® Exchange Server Analyzer Tool attempts a Domain Name System (DNS) query against the configured DNS servers for each Exchange Server computer. This connection is made by using a custom object processor that performs a name resolution request and analyzes the results. If the Exchange Server Analyzer does not receive an Internet Protocol (IP) address as part of the query results, an error is displayed.

This error indicates that an Exchange Server computer was not found in DNS. Both Exchange Server and the Active Directory® directory service require correctly configured and healthy DNS to operate correctly. DNS registration and resolution issues can have widespread effects on the ability to send, receive, and deliver messages.

You must configure DNS correctly to ensure that Active Directory and Exchange Server will function correctly. For a more in-depth treatment of DNS configuration for Active Directory, see the Microsoft Knowledge Base article 237675, "Setting Up the Domain Name System for Active Directory" (

To correct this error

  1. Review the following configuration items to ensure that DNS is healthy and that the Exchange Server DNS entries will be registered correctly:

    • DNS IP configuration

    • Dynamic zone updates

    • DNS forwarders

  2. Check for the existence of a Root Zone entry. View the Forward Lookup zones in the DNS Management console. There should be an entry for the domain. Other zone entries may exist. There should not be a dot (".") zone. If the dot (".") zone exists, delete the dot (".") zone. The dot (".") zone identifies the DNS server as a root server. Typically, an Active Directory domain that needs external (Internet) access should not be configured as a root DNS server. Manually reregister the Exchange Server IP address using Ipconfig /registerdns on the directory server after you delete the dot ("."). The Netlogon service may also need to be restarted.

  3. Manually repopulate Exchange Server DNS entries using netdiag /fix on the Exchange Server computer.

For more information about using DNS with Active Directory, see the Microsoft Knowledge Base article 323418, "How To Integrate DNS with an Existing DNS Infrastructure If Active Directory Is Enabled in Windows Server 2003" (

For more information about troubleshooting DNS and Active Directory issues, see the Knowledge Base article 260371, "Troubleshooting Common Active Directory Setup Issues in Windows 2000" (