Event ID:2130
Source:MSExchange ADAccess
Message:Process %1 (PID=%2). Exchange Active Directory Provider could not find an available domain controller in domain %3. This event may be caused by network connectivity issues or configured incorrectly DNS server. This event may also occur if you have not configured correctly your multiple Active Directory sites.

This Error event indicates that all domain controllers in the domain specified in the event description are down or unreachable. This event may occur for one or more of the following reasons:

  • Network issues prevent the Active Directory® provider from finding an available domain controller.

  • The DNS server is configured incorrectly.

  • Active Directory sites are configured incorrectly. This would be a problem only for topologies that include multiple Active Directory sites.

User Action

To resolve this error, perform one or more of the following steps:

  • Use the Ping or PathPing command-line tools to test basic connectivity from the Exchange server to one of the domain controllers. Use Ping to isolate network hardware problems and incompatible configurations. Use PathPing to detect packet loss over multiple-hop trips. For more information, see Microsoft Knowledge Base article 325487, How to troubleshoot network connectivity problems.

  • Make sure that all the domain controllers in the domain are registered correctly on the DNS server. For more information, see Microsoft Knowledge Base article 247811, How Domain Controllers Are Located in Windows.

  • If you have multiple Active Directory sites, make sure that they are configured correctly. For more information, see Creating an Active Directory Site for Exchange Server.

  • Run the Dcdiag command line tool to test the domain controller health. To do this, run dcdiag /s:<Domain Controller Name> at a command prompt on the Exchange Server. Use the output of Dcdiag to discover the root cause of any failures or warnings that it reports. For more information, see Dcdiag Overview at the Microsoft Windows Server TechCenter.

If you are not already doing so, consider running the tools that Microsoft Exchange offers to help administrators analyze and troubleshoot their Exchange environment. These tools can help you make sure that your configuration is in line with Microsoft best practices. They can also help you identify and resolve performance issues, improve mail flow, and better manage disaster recovery scenarios. Go to the Toolbox node of the Exchange Management Console to run these tools now. For more information about these tools, see Toolbox in the Exchange Server 2007 Help.