Dart

Office365 Send Email using SMTP with OAuth2 Authentication

See more Office365 Examples

Demonstrates how to send email from smtp.office365.com using OAuth2 authentication. Dart

import 'package:chilkat/chilkat.dart';

void main() {
  // This example requires the Chilkat API to have been previously unlocked.
  // See Global Unlock Sample for sample code.

  // An Office365 OAuth2 access token must first be obtained prior
  // to running this code.

  // Getting the OAuth2 access token for the 1st time requires the O365 account owner's 
  // interactive authorization via a web browser.  Afterwards, the access token
  // can be repeatedly refreshed automatically (with no user interaction).

  // See the following examples for getting and refreshing an OAuth2 access token

  // Get Office365 SMTP/IMAP/POP3 OAuth2 Access Token
  // Refresh Office365 SMTP/IMAP/POP3 OAuth2 Access Token

  // First get our previously obtained OAuth2 access token.
  final jsonToken = CkJsonObject();
  jsonToken.loadFile('qa_data/tokens/office365.json');

  final mailman = CkMailMan();

  mailman.smtpHost = 'smtp.office365.com';
  mailman.smtpPort = 587;
  mailman.startTLS = true;

  // Use your Office365 email address for the SmtpUsername.
  mailman.smtpUsername = 'OFFICE365_EMAIL_ADDRESS';
  mailman.oAuth2AccessToken = jsonToken.stringOf('access_token');

  // Create a new email object
  final email = CkEmail();

  email.subject = 'This is a test';
  email.body = 'This is a test';
  email.from = 'MY_NAME <OFFICE365_EMAIL_ADDRESS>';
  email.addTo('John Doe', 'somebody@example.com');

  // Call SendEmail to connect to the SMTP server and send.
  // The connection (i.e. session) to the SMTP server remains
  // open so that subsequent SendEmail calls may use the
  // same connection.  
  try {
    mailman.sendEmail(email);
  } on ChilkatException catch (e) {
    print(e.lastErrorText);
    return;
  }

  // If SendEmail failed because of "Failed to get initial SMTP Response", then it may be 
  // a firewall or anti-virus blocking communications.
  // See https://cknotes.com/smtp-office365-com-failed-to-get-initial-smtp-response/

  try {
    mailman.closeSmtpConnection();
  } on ChilkatException {
    print('Connection to SMTP server not closed cleanly.');
  }

  print('Mail Sent!');
}