The following error is logged when starting the Archive Manager Data Load Service and a MAPI Data Loader is configured:
Failed to process MAPI
System.NullReferenceExemption: Object reference not set to an instance of an object.
A mailbox for the journaling account is not present in the same domain as Archive Manager. If the mailbox exists in a forest that is not the same as the location of Archive Manager machine then the DL may return the value as NULL.
Create a journaling mailbox if one does not exist and ensure the Archive Manager Active Directory Connector Service has found and added the mailbox.
This issue may also be caused by a bug found in version 4.7 that was resolved in Archive Manager 4.8 If the mailbox exists in a forest that is not the same as the location of Archive Manager machine.
