The SMTPClient object supports the following authentication types:
-
GSSAPI
-
LOGIN
-
NTLM
-
PLAIN
-
XOAUTH2
You can specify which authentication type to be used via the SMTPClient AuthType property.
The MimeMessage object supports to add an email address to the "Reply To" field of the email using the AddReplyTo function, and reset the "Reply To" field using the Reset function.