3565075 - Option "Test Email" in CDC Admin Console fails with error "5.7.57 Client not authenticated to send mail. Error: 535: 5.7.139 Authentication unsuccessful, the request did not meet th criteria to be authenticated successfully."

In Customer Data Cloud (CDC) Admin console > Administration > Email Providers, testing a new SMTP relay setup fails with errors below:

• Attempt 1: Failed to connect to smtp server, 535: 5.7.139 Authentication unsuccessful, the request did not meet the criteria to be authenticated successfully. Contact your administrator.
• Attempt 2: 5.7.57 Client not authenticated to send mail. Error: 535: 5.7.139 Authentication unsuccessful, the request did not meet the criteria to be authenticated successfully. Contact your administrator.

• SAP Customer Data Cloud
• SMTP
• Email Providers

gigya, smtp, email, providers, relay, error, 5.7.57, 535, 5.7.139, test, client, not, authenticated, send, authentication, unsuccessful, meet, criteria , KBA , CEC-PRO-CON , Admin Console (Settings, Administration, Queries / Reports) , Problem