Symptoms

When trying to send an email from a Smartform, the following error occurs.

The SMTP server requires a secure connection or the client was not authenticated. The server response was: 5.7.0 Authentication required. 

Emails from Workflows are able to send. 
 

Diagnoses

N/A
 

Resolution

From the Workspace > Environment Library, we set the Mail Server field as default and removed the port number from the value such that:
from: MAIL SERVER]: PORT]
to: bMAIL SERVER]