codeigniter email sent to spam

Question

my model:

<?php
class email_model extends CI_Model {

    function __construct()
    {
        // Call the Model constructor
        parent::__construct();
    }

        public function sendEmail($from = null, $to = null, $subject = null, $message = null){

            $this->load->library('email');

            $config['protocol'] = 'sendmail';
            $config['mailpath'] = '/usr/sbin/sendmail';
            $config['charset'] = 'utf-8';
            $config['mailtype'] = 'html';
            $config['wordwrap'] = TRUE;

            $this->email->initialize($config);

            $this->email->from('email@mydomain.com', 'Website name');

            $this->email->to($to);

            $this->email->subject($subject);

            $this->email->message($message);

            $this->email->send();

        }
}

my domain is hosted on GoDaddy also i have created an email there and redirect it to my gmail email...

why does my email is sent to spam folder and not on Inbox?

EDIT: my email content is basically an invitation welcome

Hello $email

$website has invited you to join the website

to join visit the following link

$link_goes_here

Thanks, the team

Answer 1

If you are using HTML to display your mail, you have to ensure that your mail is sent with valid html. You can validate your mail here: http://validator.w3.org/

Answer 2

如果是这样，请与我们联系。.也许您可以尝试通过Amazon SES发送电子邮件，所以google / yahoo认为它不是垃圾邮件。