Unable to send SMTP Email
This article provides a solution to an error that occurs when try to send mails via your own SMTP server from a newly created Flow app.
Applies to: Microsoft Dynamics 365
Original KB number: 4535859
You try to send mails via your own SMTP server from a newly created Flow app, but you meet a problem while setting up the connection.
SSL (Secure Sockets Layer) connection isn't enabled.
To fix this issue, you could request to enable the SSL connection and check the security settings for your account. If you enabled two-step verification, try using your app password. Otherwise, enable access for less secure apps.