Email Not Received Outside of Website Domain

PHP Code:

        $this->load->library('email');
        $config['protocol']    = 'smtp';
        $config['smtp_host']    = 'domain here';
        $config['smtp_port']    = '25'; // try also yours
        $config['smtp_timeout'] = '7';
        $config['smtp_user']    = 'email';
        $config['smtp_pass']    = 'email pass';
        $config['charset']    = 'utf-8';
        $config['newline']    = "\r\n";
        $config['mailtype'] = 'html';
        $config['validation'] = FALSE;
        $this->email->initialize($config);
        $this->email->from('[email protected]', 'title here');
        $this->email->to('to email');
        $this->email->subject('test email');
        $this->email->message('
        <h2>hallo world</h2>
        ');
        $this->email->send(); 


i use this one without ssl and its working fine...  for CI3