Q: Sending an email using Office 365 SMTP and OAuth2 authentication
“AZURE setup”
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- Register the app with Redirect URI = “http://localhost:3017”.
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- Goto “API permissions” to add permissions. For this SMTP and OAuth2 authorization flow, we’ll add the following “Delegated permissions”:
- offline_access
- openid
- SMTP.Send
- IMAP.AccessAsUser.All is there because of a previous test (not needed for SMTP)
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- To add a Delegated permission, click ‘+ Add a permission’ and select ‘Microsoft Graph’
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- Select ‘Delegated permissions’
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- Search for the different permissions, select and click ‘Add Permissions’.
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4) Go to “Certificates & secrets” and add a new client secret.
- Important, the ‘Value’ field is the Client Secret which we need later during the setup in Limagito File Mover. This Value is only fully visible just after creation!
- Do not use the Secret ID (common mistake).
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5) In “App registrations”, go to “Endpoints” (located to the right of the “+ New registration” link. Note your endpoints for “OAuth 2.0 authorization endpoint (v2)” and “OAuth 2.0 token endpoint (v2).
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“Microsoft 365 admin center setup”
- Important, go to your Microsoft 365 admin center (this is NOT Azure).
- Go to your Active users.
- Click on a user to find the “Manage email apps” link under the Mail Tab. See Microsoft 365 Manage Email Apps.
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- Be sure ‘Authenticated SMTP’ is enabled
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- When not enabled you’ll receive the following error message after trying to send an email using Limagito File Mover:
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“Using a shared mailbox?”
In case you want to send emails using a shared mailbox:
- Open Microsoft 365 admin center setup
- Select ‘Teams & “groups”
- Click “+ Add a shared mailbox”
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- Click “Add members to your shared mailbox”
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- Search for members and add. The account you used previously during the ‘App registration’ in Azure must be added as member.
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- If the shared mailbox member is not correct, you’ll receive the following error:
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“Limagito File Mover setup”
- We’ll be using the Office 365 SMTP to send emails from our ‘Rule Events’ option.
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- We enabled the ‘On Success ‘ event and enabled ‘Enable Mail’:
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- Office 365 SMTP Server setup:
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- Adjust the Security setup:
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1) Fill in the correct Authorization and Token Url from previous “Azure setup”
2) Enter Application Client ID and Client Secret Value from previous “Azure setup”
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3) Adjust your scope to: openid profile offline_access https://outlook.office365.com/SMTP.Send
- Provide a SPACE separated list of scopes.
- Important: The offline_access scope is needed to get a refresh token.
4) Set Redirect URI to: http://localhost:3017/
5) Set Redirect Port to 3017
- This should be the port in the localhost callback URL for your app.
- The callback URL would look like “http://localhost:3017/”, if the port number is 3017.
- The redirect must go to http://localhost
- It must be localhost and it cannot be “https”.
Next, click on the <GET> button.
Should ‘Windows Defender’ popup, please <Allow access>.
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Your browser will open and ask you for ‘Confirmation’.
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Follow the routine in your browser and accept the authorization request.
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Now you can close the browser. The ‘Refresh’ and ‘Access’ Token in the OAuth2 Setup should contain values. Click <Save>.
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- Try your setup using the test button
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Some extra information: ‘Explaining OAuth2 Authentication’.
The OAuth2 Get Token button does a couple of things:
- It starts the OAuth2 Authentication process.
- Returns a URL that should be displayed in a browser.
- Starts a background thread to receive the redirect callback from the browser.
The flow of control is like this:
- The browser (popped up and displayed by our file mover) automatically navigates to the URL provided by Start Authentication.
- The user interactively authorizes the access. In doing so, the response sent back to the browser is a redirect to http://localhost:<someport>/
- The browser receives the response, and redirects to the http://localhost:<someport>/
- The background thread (= temporary HTTP server using <someport>) is the thing that is listening at and receives the response, and then your OAuth2 is completed.
The redirect must go to http://localhost:<someport>/. It must be localhost, and it cannot be “https”. If you defined your application’s redirect URL to a web address such as “https://yourdomain.com/something…”, then the background thread is just sitting there waiting for the callback, which never happens (because it went to your web server).
#office365 #mft #Filetransfer #smtp
If you need any info about this “Office 365 SMTP”, please let us know.
Best regards,
Limagito Team