mail error

[eluser]runrun[/eluser]

Code:

A PHP Error was encountered

Severity: Warning

Message: mail() [function.mail]: SMTP server response: 550 <[email protected]>, Recipient unknown

Filename: libraries/Email.php

Line Number: 1519

Can you help me fix this please ?

This is my email code. And I use windows hosting.

Code:

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

            $email=$this->input->post('email');
            $name=$this->input->post('name');
            $subject=$this->input->post('subject');
            $message=$this->input->post('message');

            $this->email->from($email, $name);
            $this->email->subject($subject);
            $this->email->message($message);
            $this->email->to('[email protected]');
            $this->email->send();
            $this->load->view('contact_success.php');