Put on header of message sent using MAPI the MAPI information like Exchange

Received: ; Thu, 6 Aug 2020 08:53:20 -0300 From: To: Subject: RES: Archive Date: Thu, 6 Aug 2020 08:53:20 -0300 Reply-To: Message-ID: <57fe682dc6514405beffc6ed9e3f6974@> MIME-Version: 1.0 Content-Type: multipart/alternative; boundary=d1c31e42d7164cb296dd0c2e91cdbbbf X-SmarterMail-TotalSpamWeight: 0 (Authenticated) It's not possible to identify if the message has sent from MAPI or WEBMAIL.