XADM: Error Message: Event ID 1043 Source MSExchangeDS (262433)



The information in this article applies to:

  • Microsoft Exchange Server 5.5

This article was previously published under Q262433

SYMPTOMS

If the Knowledge Consistency Checker runs by default on a directory replication server or if you start the Knowledge Consistency Checker (in the server Directory Service properties, click Check Now on the General tab) on a server that has directory replication connectors to other sites, the following error message is logged in the Microsoft Windows NT Event Viewer application event log:
Event ID: 1043
Source: MSExchangeDS

Type: Error
Category: Knowledge Consistency Description:
The knowledge consistency checker has detected that site /O=Organization/OU=Site can be replicated to this directory service from more than one source. Remove one source and run the knowledge consistency checker again. c1030b0f

CAUSE

This issue can occur if the directory replication connectors are set up in a configuration that creates a message loop between the directory replication servers within the Exchange Server organization. The Knowledge Consistency Checker detects duplicated knowledge of Exchange Servers through the duplicate directory replication connectors.

For example, if you have Site A, Site B, and Site C set up with directory replication connectors as follows
  • Site A <==> Site B
  • Site B <==> Site C
  • Site C <==> Site A
this setup creates a logical loop for the directory replication messages and generates the Knowledge Consistency Checker error message.

RESOLUTION

To resolve this issue, remove one of the directory replication connectors that creates the loop between the sites.

MORE INFORMATION

Each Exchange Server computer in a site runs a Knowledge Consistency Checker check every three hours to verify the Exchange Server computer's knowledge of other Exchange Server computers in the site. To verify this knowledge, the Exchange Server computer contacts another Exchange Server computer in the site to compare information. Which Exchange Server computer is contacted depends on the server's alphanumeric name. The Knowledge Consistency Checker is remote procedure call (RPC) based and operates only within the site.

Modification Type:MinorLast Reviewed:4/21/2005
Keywords:kbprb KB262433