Access to path is denied This code is working properly in my system but in web server it is showing this error Here is my code:

protected void Button1_Click(object sender, EventArgs e)
    {
        string id = Request.QueryString["id"];
        i++;
        if (upimage.HasFile)
        {
            if (CheckFileType(upimage.FileName))
            {

                string ext = Path.GetExtension(upimage.FileName);
                string filename = Path.GetFileName(upimage.FileName);
                string name = Server.MapPath("~/upload/") + s + i + ext;
                upimage.SaveAs(name);
                SqlDataSource1.InsertParameters["id"].DefaultValue = id;
                SqlDataSource1.InsertParameters["path"].DefaultValue = name;
                SqlDataSource1.Insert();
            }

        }

    }



    bool CheckFileType(string filename)
    {
        string ext = Path.GetExtension(filename);
        switch (ext.ToLower())
        {
            case ".gif":
                return true;
            case ".png":
                return true;
            case ".jpg":
                return true;
            case ".jpeg":
                return true;
            default:
                return false;
        }
    }

    void Page_PreRender()
    {
        string upfolder = MapPath("~/upload");
        DirectoryInfo dir = new DirectoryInfo(upfolder);
        DataList1.DataSource = dir.GetFiles();
        DataList1.DataBind();
    }

    protected void Delete_File(object sender, DataListCommandEventArgs Args)
    {

        File.Delete(Server.MapPath("~/upload")+ Args.CommandName);
        Page_PreRender();

    }

    protected void Page_Load(object sender, EventArgs e)
    {
        Class1.i = 0;
    }
        public Int32 return_number_class()
{
Class1 s = new Class1();
return s.return_number();
}
    public class Class1
{
        public Class1()
        {

        }
    public  static Int32 i =0 ;
    public Int32 return_number()
    {
        i++;
        return i;
    }

}