Configuring Microsoft 365 SMTP Connector for Outgoing Email

Overview

Ubersmith supports using Microsoft 365's SMTP Connector to send outgoing email. This configuration allows you to leverage Microsoft 365's email infrastructure to improve delivery reliability and reduce the risk of emails being flagged as spam. This article will guide you through the process of configuring Ubersmith's mail container to use Microsoft 365 SMTP Connector for outgoing email using IP-based authentication.

Prerequisites

• Microsoft 365 account with SMTP Connector set up to allow IP-based authentication
• Static IP address for your Ubersmith instance

Step 1: Configure Mail Container

1. Log in to your Ubersmith instance and navigate to Settings > Email Settings.
2. For each brand configured in Ubersmith, ensure the Email sending settings options are configured to use SMTP as the Method and mail as the SMTP Host.
3. Leave the SMTP Username and SMTP Password fields blank.

Step 2: Configure IP-Based Authentication

1. Follow Microsoft's documentation to configure the SMTP Connector using IP based authentication.
2. Ensure that your Microsoft 365 account is configured to allow IP-based authentication for the static IP address of your Ubersmith instance.

Step 3: Update Mail Container Configuration

1. Update the docker-compose.override.yml file to include the following environment variable:

mail:
  ...
  environment:
    - "POSTFIX_RELAYHOST=[yourdomain-com.mail.protection.outlook.com]:25"

Replace yourdomain-com.mail.protection.outlook.com with the appropriate hostname of your Microsoft 365 SMTP server.

Step 4: Recreate the Mail Container

1. Recreate the mail container to apply the configuration changes.

docker compose up -d mail

Verification

1. Test outgoing email by sending a test email from Ubersmith.
2. Check the logs for Ubersmith's mail container using journalctl: journalctl -t ubersmith/mail -f
3. Verify that the email is delivered successfully and that the email headers show the Microsoft 365 SMTP server as the sending server.

If you encounter any issues during the configuration process, please contact our support team for assistance.