Getting session_start warnings on header and footer of webpage

Question

I keep receiving this warning on my web page and I'm not really sure what to do to fix this issue can someone provide me with a detailed example on how to remove this warning.

Header

Warning: session_start() [function.session-start]: open(/home/content/58/7146558/tmp/sess_n8fne7p2utq3e17monl6fo0lh5, O_RDWR) failed: No such file or directory (2) in /home/content/58/7146558/html/upload/include/fgcontactform.php on line 63

Warning: session_start() [function.session-start]: Cannot send session cache limiter - headers already sent (output started at /home/content/58/7146558/html/upload/include/fgcontactform.php:63) in /home/content/58/7146558/html/upload/include/fgcontactform.php on line 63

Footer

Warning: Unknown: open(/home/content/58/7146558/tmp/sess_n8fne7p2utq3e17monl6fo0lh5, O_RDWR) failed: No such file or directory (2) in Unknown on line 0

Warning: Unknown: Failed to write session data (files). Please verify that the current setting of session.save_path is correct () in Unknown on line 0

Here is the code:

<?PHP
 /*
   Contact Form from HTML Form Guide

This program is free software published under the
terms of the GNU Lesser General Public License.

This program is distributed in the hope that it will
be useful - WITHOUT ANY WARRANTY; without even the
implied warranty of MERCHANTABILITY or FITNESS FOR A
PARTICULAR PURPOSE.

@copyright html-form-guide.com 2010
*/
require_once("class.phpmailer.php");

/*
Interface to Captcha handler
*/
class FG_CaptchaHandler
{
function Validate() { return false;}
function GetError(){ return '';}
}
/*
FGContactForm is a general purpose contact form class
It supports Captcha, HTML Emails, sending emails
conditionally, File atachments and more.
*/
class FGContactForm
{
var $receipients;
var $errors;
var $error_message;
var $name;
var $email;
var $message;
var $from_address;
var $form_random_key;
var $conditional_field;
var $arr_conditional_receipients;
var $fileupload_fields;
var $captcha_handler;

var $mailer;

function FGContactForm()
{
    $this->receipients = array();
    $this->errors = array();
    $this->form_random_key = 'HTgsjhartag';
    $this->conditional_field='';
    $this->arr_conditional_receipients=array();
    $this->fileupload_fields=array();

    $this->mailer = new PHPMailer();
    $this->mailer->CharSet = 'utf-8';
}

function EnableCaptcha($captcha_handler)
{
    $this->captcha_handler = $captcha_handler;
    session_start();
}

function AddRecipient($email,$name="")
{
    $this->mailer->AddAddress($email,$name);
}