curl -v  smtp://hkie7apprelay.asia.intl.cigna.com  --mail-from [email protected] --mail-rcpt [email protected] --upload-file email.txt

email.txt
>
From: John Smith <[email protected]>
To: Joe Smith <[email protected]>
Subject: an example.com example email
Date: Mon, 7 Nov 2016 08:45:16

Dear Joe,
Welcome to this example email. What a lovely day.
<

from: John Smith <[email protected]>

Subject: an example.com example email

To: Joe Smith

Content:

Dear Joe,

Welcome to this example email. What a lovely day.