使用Cron作业和Codeigniter结果

Question

现在我已经尝试使用cron job通过调用控制器来自动升级我的数据库中的用户。

但这是我不断收到的电子邮件，我不知道哪里出了问题。

如果有人能帮我纠正，我会非常感激

 int maxRange = 20;
 int yInterval = 5;
 var minRange = (maxRange * -1);
 area.AxisY.Minimum = minRange;
 area.AxisY.Maximum = maxRange;
 area.AxisY.LabelStyle.Format = "#";
 area.AxisY.Interval = yInterval;
 int yVal = minRange;
 while (yVal <= maxRange)
 {
    area.AxisY.CustomLabels.Add(yVal - 0.5, yVal + 0.5, yVal.ToString());
    yVal += yInterval;
 }

我花时间从控制器中删除所有空间，但似乎没有任何工作，这里是我的控制器

<div style="border:1px solid #990000;padding-left:20px;margin:0 0 10px 0;">

<h4>A PHP Error was encountered</h4>

<p>Severity: Warning</p>
<p>Message:  session_start(): Cannot send session cookie - headers already sent</p>
<p>Filename: Session/Session.php</p>
<p>Line Number: 143</p>


        <p>Backtrace:</p>


                        <p style="margin-left:10px">
                        File: /home/esclubso/public_html/application/core/My_Controller.php<br />
                        Line: 8<br />
                        Function: __construct                   </p>




                        <p style="margin-left:10px">
                        File: /home/esclubso/public_html/application/controllers/Welcome.php<br />
                        Line: 6<br />
                        Function: __construct                   </p>






                        <p style="margin-left:10px">
                        File: /home/esclubso/public_html/index.php<br />
                        Line: 316<br />
                        Function: require_once                  </p>

我的欢迎控制器

<?php
class My_Controller extends CI_Controller{
    public $layout;
    public $layout2;
    public $admin_layout;
    public $user_layout;
    public function __construct(){
        parent::__construct(); // this is the line 8

        $this->layout   ='master';

        $this->user_layout  ='dashboard/user_dashboard/master';
        $this->admin_layout ='dashboard/admin_dashboard/master';
        $this->load->library('Session_checker');

        $this->load->model('Action');
        $this->load->model('Login_user');
        $this->load->model('Reaction');
        $this->load->model('Upgrade_account');
        $this->load->model('Manage_user');
    }
}