Topic Last Modified: 2005-11-17

The Microsoft® Exchange Server Analyzer Tool queries the Active Directory® directory service to determine the value of the fSMORoleOwner attribute of the root of domain directory partition in the Domain Naming Context. For example, in a domain called, fSMORoleOwner for the primary domain controller (PDC) emulator is an attribute of DC=contoso,DC=com. The Exchange Server Analyzer then tries to open a Lightweight Directory Access Protocol (LDAP) connection to TCP port 389 on the domain controller that currently holds this role. If the Exchange Server Analyzer cannot connect to this domain controller, an error is displayed.

The PDC emulator serves as primary domain controller for compatibility with earlier Microsoft Windows® operating systems. Microsoft Windows 2000 Server and Microsoft Windows Server™ 2003 interoperate with Microsoft Windows NT® workstations, member servers, and backup domain controllers. The PDC in a Microsoft Windows NT 3.51 or Microsoft Windows NT 4.0 domain is responsible for the following:

At any time, the PDC emulator master role can be assigned to only one domain controller in each domain.

To correct this error

  1. Verify that the directory server specified in the error is online and accessible by Exchange servers in your organization.

  2. If this directory server has been decommissioned, you must assign the PDC emulator role to another domain controller.

For more information about transferring the PDC emulator role from one domain controller to another domain controller, see the following Microsoft Knowledge Base articles: