I was recently assisting a colleague with an issue he had experienced with a Microsoft Exchange 2003 to Microsoft Exchange 2010 migration. The migration had completed correctly, however for an unknown reason you could not send e-mail to any mail-enabled public folders, despite whether these were created newley from within the Exchange Management Console or were replicated as a part of the migration. All of the mail-enabled public folder properties were correct, including permissions, and Exchange 2010 Service Pack 1 had also been applied. When e-mailing a mail-enabled public folder from an external network no NDR was produced, however when e-mailing from the internal network the following NDR was returned:
#554 5.2.0 STOREDRV.Deliver.Exception:ObjectNotFoundException; Failed to process message due to a permanent exception with message The Active Directory user wasn’t found. ObjectNotFoundException: The Active Directory user wasn’t found. ##
After performing some research it turned out this is a known problem with Exchange 2010 migrations as detailed here. The issue occurs due to the legacy administrative group (First Administrative Group) being empty following the migration. To resolve this issue perform the following actions:
1. Open ADSI Edit on either a domain controller or your Microsoft Exchange 2010 server.
2. Navigate to the “CN=Servers” ADSI attribute by locating the below path, I have also included a screenshot of the location to help identify the attribute:
CN=Servers,CN=First Administrative Group,CN=Administrative Groups,CN=First Organization,CN=Microsoft Exchange,CN=Services,CN=Configuration, DC=domain,DC=local
3. Right click the “CN=Servers” container and select delete. Click OK when prompted in order to confirm the action. Note: Do not delete the top level container “First Administrative Group”, this is against Microsoft best practices and may have a negative affect on your Exchange organisation.
4. Ensure replication of your Active Directory database has occurred to all domain controllers and then attempt sending an e-mail to one of your mail-enabled public folders. You should now find e-mail makes it way to these folders as expected.
For more information on this issue, please see the following URL: http://msexchangeteam.com/archive/2010/05/05/454821.aspx