· Dec 11, 2020

%Net.SMTP and Gmail

I am trying to send email via

  • I am using an object of %Net.SMTP to do so.
  • I am giving it an object of class %Net.Authenticator to provide credentials to the gmail server.
  • I am not encoding the user name or password.
  • I have set the UseSTARTTLS property to 1
  • I have set the SSLConfiguration property to “API”
  • Since I am using TLS, I have set the port to be 587
  • I am using an object of %Net.MailMessage for the message
  • I am passing it to the Send method of the %Net.SMTP object to send the msg.
  • I get the following error: ERROR #6033: Error response to SMTP MAIL FROM: 530 5.7.0 c62sm7543742pfa.116 - gsmtp.

Are there any ideas of what I may be doing wrong?

Discussion (3)2
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Hi Anna,

This error points to an Authentication issue. I see only two areas where the problem could be:

1) Incorrect username/pw (unlikely as you probably already checked it)

2) Mismatched Certificate

I assume you created an SSL Configuration in System Administration on the Server that is sending the email. Did you add any Certificate file to that configuration? If you did, I would check the Common Name (CN) - is it set to ""?

I found a thread in which a setting in the Postfix configuration on the local server would cause a substitution of the CommonName with the Fully Qualified Domain Name obtained during DNS lookup - which was different from "" and resulted in a similar error: