System.Runtime.InteropServices.COMException (0x8007203A): The server is not operational. error is thrown
The Journal Mailbox is not being processed, and is growing.
The Data Loader service is attempting to lookup the LegacyExchangeDN in AD and is unable to gather the information.
Change the login information in the MAPI Data Loader properties on the Admin Website to reflect the Legacy Exchange DN rather than the account name.
Restart the Data Loader service.
To find find the Legacy Exchange DN for ArchiveMgr_Journal account the following SQL query needs to be run against the in Archive Manager SQL Database.
select ActiveDirectoryExchangeLegacyDN from login where LoginName like 'ArchiveMgr_Journal'
where ArchiveManager is the ArchiveManager database's name and ArchiveMgr_Journal is the ArchiveMgr_Journal account's name.