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Objective-C

Office365 Send Email using SMTP with OAuth2 Authentication

See more Office365 Examples

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

Chilkat Objective-C Downloads

Objective-C
#import <CkoJsonObject.h>
#import <CkoMailMan.h>
#import <CkoEmail.h>

BOOL success = NO;

// 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.
CkoJsonObject *jsonToken = [[CkoJsonObject alloc] init];
success = [jsonToken LoadFile: @"qa_data/tokens/office365.json"];

CkoMailMan *mailman = [[CkoMailMan alloc] init];

mailman.SmtpHost = @"smtp.office365.com";
mailman.SmtpPort = [NSNumber numberWithInt:587];
mailman.StartTLS = YES;

// Use your Office365 email address for the SmtpUsername.
mailman.SmtpUsername = @"OFFICE365_EMAIL_ADDRESS";
mailman.OAuth2AccessToken = [jsonToken StringOf: @"access_token"];

// Create a new email object
CkoEmail *email = [[CkoEmail alloc] init];

email.Subject = @"This is a test";
email.Body = @"This is a test";
email.From = @"MY_NAME <OFFICE365_EMAIL_ADDRESS>";
success = [email AddTo: @"John Doe" emailAddress: @"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.  
success = [mailman SendEmail: email];
if (success != YES) {
    NSLog(@"%@",mailman.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/

success = [mailman CloseSmtpConnection];
if (success != YES) {
    NSLog(@"%@",@"Connection to SMTP server not closed cleanly.");
}

NSLog(@"%@",@"Mail Sent!");