According to the 4D manual, it suggests that it is possible using SMTP_Body, to create a multi part email with an HTML part and an optional text part, something which is a good practice to do.
The 4D manual states:
“To combine sending the message in HTML with a replacement option, you can just add together the values. For example, you can pass 1+4 in option to replace the body and send the message in HTML.”
Which suggests that you can send multi-part, HTML and Text emails, but there are no samples showing how to do this, and passing 1+4 in the options of SMTP does not accomplish this.>Product :4D - 4D Server
I am using 4D 17.
OS : Mac OS X