Why does the Get_Email_Envelope_1 operator only offer IMAP, POP3, IMAP-SSL, and POP3-SSL protocols and not the SMTP protocol. Here is a screenshot:
Release : 4.3
Component : Process Automation
The reason is that the SMTP protocol has one function only and that is to send outgoing emails. It cannot view an incoming email in the inbox, gather a list of the emails in a folder on the email server, or provide any information about the headers (envelope) of emails in the inbox. The other protocols listed in the screenshot are the only ones that can review the email inbox and return any information about emails received.
There may be other operators in the ITPAM workflow that send emails and those will use the SMTP protocol. But the one illustrated in the screenshot, Get_Email_Envelope_1 returns information about emails received on the email server and so the SMTP protocol cannot be used for this specific operator.