Your Exchange server has an accepted Domain named "domain.com" that is your own e-mail domain. Your internal users have SMTP addresses like JDoe@domain.com. There exists an external person that shown in the GAL as Chief of ZZZ European Department. When any internal user receives a message from that person, the From field contains Big Boss. Big Boss is a display name of the sender as it set on his side. But you'd like to see there Chief of ZZZ European Department as he is recorded in your Global Address List.
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