Microsoft SMTP OAuth2 set-up

This document provides step-by-step instructions for creating OAuth2 credentials for SMTP authentication using Google and Microsoft platforms. This document assumes the reader has basic familiarity with the Microsoft Azure Portal.

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1. Register an application

• Go to https://portal.azure.com/ and sign in with an account that has administrative privileges for Microsoft Entra ID
• In the left menu, select App registrations
• Configure the application:

• Use the following information:
  • Name: Enter a descriptive name (e.g. Gateway SMTP App)
  • Supported account types: Accounts in this organizational directory only
  • Redirect URI: The redirect URI specifies where the authorization server should send the user back after successfully authenticating to return an access token to their email account.
    • Type: Web
    • URL: http://<host>:<port>/credentials/generic/authorize/callback
      • Host: DNS name or IP address of your PADS4 Web Portal
      • Port: Optional, if your PADS4 instance does not use the default ports for HTTP or HTTPS.
• Once the information has been filled in, click on “Register”.
• Now on the app Overview page, copy the Application(client) ID and Directory (tenant) ID. These are required for your gateway configuration.

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2. Create client secret

• Go to Certificates & secrets > Client Secrets > New client secret.
• Add a description (e.g., “SMTP Secret”) and select an expiration period (e.g., 24 months).
• Click Add, then immediately copy the value of the client secret. Note: This value is only shown once, and you will not be able to retrieve it after leaving this page. If you lose it, you’ll need to generate a new one. This is your “ClientSecret”.
• Store it securely, as it grants access to your application

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3. Configure API permissions

• From the left-hand navigation of your application’s overview page, click on API permissions > +Add a permission
• Select Microsoft Graph

• Select Delegated permissions > Search for offline access

• Add offline_access permission.

• Search for permission SMTP.Send and add this permission as well.

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5. Configuration in PADS4

To begin:

• Open your web browser.
• Navigate to the PADS4 server URL (either a DNS name or IP address).
• Log in using an Administrator account.

Once logged in:

• Click on Dashboard.
• Use the Toggle Sidebar button at the top-left of the screen.
• Navigate to Credentials.
• Then select Providers.
• Click on New

• Select SMTPOAuth2

• Fill in the information as follows:
  • App name: Represent the name of your provider in PADS4 (can be any value)
  • SMTP Provider: Microsoft
  • App (client) ID: Application ID from Azure/Entra ID described at the end of step 1
  • Client Secret: Retrieved from Azure/Entra ID described at the end of step 1
  • Tenant ID: Directory ID from Azure/Entra ID described at the end of step 1
• Click on create
• Now go to the overview page and select the SMTP provider that you have just configured.
• Click connect, select your user account and grant the request access.

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How to use this set up in the SMTP configuration.

Once logged in:

• Click on Home.
• Use the Toggle Sidebar button at the top-left of the screen.
• Navigate to Config.
• Then click Edit

• Turn on Use OAuth
• Select your just configured OAuth provider and Username.
• Fill in the rest of your SMTP server and address details
• You can then test the connection at the bottom left which will return a green checkmark if the connection is properly configured.