External SMTP Authentication Configuration

Dear Indico team,
We currently utilize an external SMTP server, and use password for authentication. We encountered some challenges when I tried to get more than one email user authenticated so that we can send reminder or any other email with different email address.

Could you kindly offer guidance on whether this can be achieved through configuration settings or if a local SMTP server is necessary? Any specific steps or recommendations you can provide would be greatly appreciated.

Thank you in advance for your assistance.

Best regards,

If the server does only accept mails from the user that authenticated, then yes, you probably should run a smpt server locally with an upstream smtp server configured as smarthost. It is the same situation as here: Email failing due to from address not being verified in Amazon SES