Topic Last Modified: 2005-11-18

The Microsoft® Exchange Server Analyzer Tool queries the Exchange_DSAccessDC Microsoft Windows® Management Instrumentation (WMI) class in the ROOT\MicrosoftExchangeV2 namespace to determine the values for the IsFast key and the IsUp key. If the value for the IsUp key is True, it indicates the directory server used by the Directory Service Access (DSAccess) component in Exchange Server is connected to the network and responding. A value of False indicates the directory server is not responding. If the value of IsFast is True, it indicates the response time of this directory server is less than two seconds. A value of False indicates the response time is more than two seconds. If the value of IsUp is True but the value of IsFast is False, an error is displayed.

To correct this error

  1. Examine the load on the domain controller and global catalog. An overloaded domain controller and global catalog can be slow to respond to Lightweight Directory Access Protocol (LDAP) calls.

  2. Make sure that there is at least one global catalog in the local Active Directory® directory service site for optimal performance.

For more information about DSAccess and directory services detection, see the Microsoft Knowledge Base article 250570, "Directory Service Server Detection and DSAccess Usage" (