win7 64位系统socket线程问题,传送一个文件到客户端,客户端openfiledialog打不开

Question

这程序在我xp电脑上可以打开openfiledialog,但在win7中打不开什么原因?这是客户端代码:
代码应该没问题的 private void ReciveMsg()
        {
            while (true)
            {
                try
                {
                    byte[] byteMsg = new byte[1024 * 1024 * 5];
                    int length = sockCleint.Receive(byteMsg);
                    //接收到数据了
                    if (length > 0)
                    {
                        //接收的是字符串
                        if (byteMsg[0] == 0)
                        {
                            
                         //string strMsg = Encoding.UTF8.GetString(byteMsg, 0, length);
                            string strMsg = Encoding.UTF8.GetString(byteMsg,1, length);
                            ShowMsg(strMsg);
                        }
                            //接收的是文件
                        else if(byteMsg[0]==1)
                        {
                            try
                            {
                                OpenFileDialog ofd = new OpenFileDialog();
                                ofd.InitialDirectory = @"F:\";
                                if (ofd.ShowDialog() == DialogResult.OK)
                                {
                                    string savePath = ofd.FileName;
                                    using (FileStream fs = new FileStream(savePath, FileMode.Create))
                                    {
                                        fs.Write(byteMsg, 1, byteMsg.Length - 1);
                                        ShowMsg("保存完毕!" + savePath);
                                    }
                                }
                            }
                            catch (Exception ex)
                            {                                ShowErro("",ex);
                                break;
                            }
                        }
                    }
                }
                catch (Exception ex)
                {                    ShowErro("",ex);
                    break;
                }
            }
        }socket