很奇怪 微软都做了些什么？[1]

前些天8月以前文件下载还能用，最近做了几次windows更新就挂了！！！！！！！！

微软你到底做了些什么？？？？？？

文件下载的代码如下：

using System;
using System.Web;
using System.Web.UI;
using System.IO;
using System.Threading;

namespace FileDownLoad4Net
{
 /// <summary>
 /// FileDown 的摘要说明。
 /// </summary>
 public class FileDown
 {
  private string m_strFullPath;
  private long m_lSpeed;
  private int m_iFactDownSpeed;
  private string m_strFileName;

  /// <summary>
  ///  下载页显示文件名
  /// </summary>
  public string FileName
  {
   get{return m_strFileName;}
   set{m_strFileName = value;}
  }
  /// <summary>
  ///  带文件名下载路径
  /// </summary>
  public string FullPath
  {
   get{return m_strFullPath;}
   set{m_strFullPath = value;}
  }
  /// <summary>
  /// 每秒允许下载的字节数
  /// </summary>
  public long Speed
  {
   get{return m_lSpeed;}
   set{m_lSpeed = value;}
  }

  /// <summary>
  /// 实际下载速度
  /// </summary>
  public int FactDownSpeed
  {
   get{return m_iFactDownSpeed;}
   set{m_iFactDownSpeed = value;}
  }
  /// <summary>
  /// 表示一个下载
  /// </summary>
  public FileDown()
  {
   //
   // TODO: 在此处添加构造函数逻辑
   //
  }
  /// <summary>
  /// 开始下载文件
  /// </summary>
  /// <returns></returns>
  public bool DownFile()
  {
   return DownFile(this.FileName,this.FullPath,this.Speed);
  }
  /// <summary>
  ///  开始下载文件
  /// </summary>
  /// <param name="p_strFileName">下载页显示文件名</param>
  /// <param name="p_strFullPath">带文件名下载路径</param>
  /// <param name="p_lSpeed">每秒允许下载的字节数</param>
  /// <returns></returns>
  public bool DownFile(string p_strFileName,string p_strFullPath, long p_lSpeed)
  {
   bool bRtn = false;

   System.Web.UI.Page p_page = (Page)System.Web.HttpContext.Current.Handler;

   //try1
   try
   {
    #region "try1"
    FileStream myFile = new FileStream(p_strFullPath, FileMode.Open,
     FileAccess.Read, FileShare.ReadWrite);
    BinaryReader br = new BinaryReader(myFile);
    //try2
    try
    {      
     #region "try2"
     //p_page.Response.Clear();
     p_page.Response.AppendHeader("Accept-Ranges", "bytes");
     p_page.Response.BufferOutput = false;
     long fileLength = myFile.Length;
     long startBytes = 0;

     int pack = 10240; //10K bytes
     //int sleep = 200; //每秒5次 即5*10K bytes每秒
     int sleep = (int)Math.Floor(1000 * pack / p_lSpeed) + 1;

     if (p_page.Request.Headers["Range"] != null)
     {
      p_page.Response.StatusCode = 206;
      string[] range = p_page.Request.Headers["Range"].Split(new char[] {'=', '-'});
      startBytes = Convert.ToInt64(range[1]);
     }