Sample full code of sending an email using MailCore2 in Objective-C

sendmailcore2objc.m

- (IBAction)sendEmail:(id)sender {
    MCOMessageBuilder *builder = [[MCOMessageBuilder alloc] init];
    
    MCOAddress *address = [MCOAddress addressWithDisplayName:@"Uplant Support" mailbox:@"noreply.uplant@gmail.com"];
    NSArray *to = [NSArray arrayWithObject:[MCOAddress addressWithDisplayName:@"Glenn Posadas" mailbox:@"admin@glennvon.com"]];
    
    [[builder header] setFrom:address];
    [[builder header] setTo:to];
    [[builder header] setSubject:@"This is a nice subject"];
    [builder setHTMLBody:@"The motherloving body."];
    
    NSData * data = [builder data];
    
    MCOSMTPSession *smtpSession = [[MCOSMTPSession alloc] init];
    [smtpSession setHostname:@"smtp.gmail.com"];
    [smtpSession setUsername:@"noreply.uplant@gmail.com"];
    [smtpSession setPassword:@"----"];
    [smtpSession setPort:465];
    [smtpSession setConnectionType:MCOConnectionTypeTLS];
    
    MCOSMTPSendOperation *smtpSender = [smtpSession sendOperationWithData: data];
    [smtpSender start:^(NSError * _Nullable error) {
        NSLog(@"Error: %@", error.localizedDescription);
    }];
}