How to Connect mySMTP with Microsoft Exchange Server 2019 (Smart Host Setup)

This setup uses a send connector with authentication to relay all outbound mail via relay.xx.xxx (from setup email)

Step 1: Open Exchange Admin Center (EAC)

1. Open your browser and go to your Exchange Admin Center:
   https://<YourExchangeServer>/ecp>
2. Log in with admin credentials.

🛠 Step 2: Create a New Send Connector

1. In the EAC, go to Mail Flow > Send Connectors.
2. Click the + (plus) icon to create a new connector.
3. Name it mySMTP or similar, and set Type to Internet.
4. Click Next.

✍️ Step 3: Configure the Smart Host

1. On the Network settings screen:
   • Select: Route mail through smart hosts
   • Click + Add, and enter:
     relayxx.xx.xxx (from setup email)
2. Click Next.

🔐 Step 4: Set Up Authentication

1. On the Smart host authentication screen:
   • Select: Basic Authentication
   • Enter your mySMTP username and password
   • Check: ✅ Offer basic authentication only after starting TLS
2. Click Next.

🖥️ Step 5: Source Server

1. Click + Add and select your Exchange server (e.g. EXCH01).
2. Click Finish to create the connector.

🧪 Step 6: Test the Connection

Send a test email from a user mailbox (e.g., using Outlook or OWA) to an external email address (e.g., Gmail or your own).

✅ Success Checklist

• 🔒 Port: 587
• 🔐 Encryption: TLS (STARTTLS)
• 👤 Auth: Basic (plain login)
• 📤 Smart Host: smtp.mysmtp.com