Set Up SMTP Credentials: Next, you'll need to set up the SMTP credentials that Postfix will use to authenticate with Exchange Online. These credentials should be stored in a file specified by the smtp_sasl_password_maps setting.
Set Up SMTP Credentials: Next, you'll need to set up the SMTP credentials that Postfix will use to authenticate with Exchange Online. These credentials should be stored in a file specified by the smtp_sasl_password_maps setting.