we upgraded cireson portal production from version 4 to version 7.4 . After the upgrade- the send email functionality is not working. Prior to the upgrade it was working with the same settings. I see the below error in the log:
Send Email Failed:The SMTP server requires a secure connection or the client was not authenticated. The server response was: 5.7.1 Client was not authenticated
This is production - we require urgent assistance. kindly suggest! Thanks