问题：服务器跟换了一个exe文件，部分客户端下载的还是之前的exe（大部分客户端正常）
同样路径方法下 下载非exe 文件正常！！！！！！

是客户端问题还是服务端问题？
是代码问题还是客户端电脑问题？
 string UpdateFile = lvUpdateList.Items[i].Text.Trim();
                        string updateFileUrl = updateUrl + lvUpdateList.Items[i].Text.Trim();
                        long fileLength = 0;

                        WebRequest webReq = WebRequest.Create(updateFileUrl);
                        WebResponse webRes = webReq.GetResponse();
                        fileLength = webRes.ContentLength;

                        lbState.Text = "正在下载更新文件,请稍后...";
                        pbDownFile.Value = 0;
                        pbDownFile.Maximum = (int)fileLength;

                        Stream srm = webRes.GetResponseStream();
                        StreamReader srmReader = new StreamReader(srm);
                        byte[] bufferbyte = new byte[fileLength];
                        int allByte = (int)bufferbyte.Length;
                        int startByte = 0;
                        while (fileLength > 0)
                        {
                            Application.DoEvents();
                            int downByte = srm.Read(bufferbyte, startByte, allByte);
                            if (downByte == 0) { break; };
                            startByte += downByte;
                            allByte -= downByte;
                            pbDownFile.Value += downByte;

                            float part = (float)startByte / 1024;
                            float total = (float)bufferbyte.Length / 1024;
                            int percent = Convert.ToInt32((part / total) * 100);

                            this.lvUpdateList.Items[i].SubItems[2].Text = percent.ToString() + "%";

                        }

                        string tempPath = tempUpdatePath + UpdateFile;
                        CreateDirtory(tempPath);
                        FileStream fs = new FileStream(tempPath, FileMode.OpenOrCreate, FileAccess.Write);
                        fs.Write(bufferbyte, 0, bufferbyte.Length);
                        srm.Close();
                        srmReader.Close();
                        fs.Close();