Hello David
You have to find all Received: from xxx by xxx headers, starting by the last one and going up. Each one includes the timestamp provided by each mail relay. It might to find where is the gap. If Outlook does not show them, you have to find a way to show the source of the message.
Example from a real mail:
Received: from xxxx
by xxxx;
Wed, 17 Apr 2024 11:28:28 +0200
Received: from xxxx
by xxxx
for xxxx; Wed, 17 Apr 2024 11:28:28 +0200 (CEST)
Received: from xxxx
by xxxx
for xxxx; Wed, 17 Apr 2024 11:28:28 +0200 (CEST)
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Marc Rauzier
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