Two objects in the Directory have the same proxy - /DC=com/DC=abc/DC=Server/CN=Users/CN=Microsoft Schedule+ Free/Busy Connector (Server) and /DC=com/DC=abc/CN=Users/CN=Microsoft Schedule+ Free/Busy Connector (Server).
Check ME318774 and TB218247 if you get this on an Exchange 2007 server.
As per Microsoft: "This warning event indicates that there are two objects in Active Directory that have the same e-mail address. Such a situation can lead to mail delivery failures and should be resolved immediately. There could be several causes for this situation. For example, during migration, the Active Directory Connector (ADC) might create duplicate objects". See MSEX2K3DB for additional information about this event.
According to Microsoft, this problem may occur in situations where the hotfix that is described in ME328905 is installed on the server, and where a NULL value is incorrectly dereferenced in Phatq.dll. See ME811302 and ME555419 for more information on this event.
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