Zipping Files and Downloading them Using SaveAs Dialog

protected void DownloadSelectedFiles_Click(object sender, EventArgs e)
        {
            string path = String.Empty;
            string zipFilePath = @"C:MyZipFile.zip";

            ZipOutputStream zipStream = new ZipOutputStream(File.Create(zipFilePath));
            byte[] buffer = new byte[4096];

            foreach (GridViewRow row in gvFiles.Rows)
            {
                bool isSelected = (row.FindControl("chkSelect") as CheckBox).Checked;

                if (isSelected)
                {
                    path = (row.FindControl("lblUrl") as Label).Text;

                    ZipEntry entry = new ZipEntry(Path.GetFileName(path));
                    entry.DateTime = DateTime.Now;

                    zipStream.PutNextEntry(entry);

                    using (FileStream fs = File.OpenRead(path))
                    {
                        int sourceBytes;
                        do
                        {
                            sourceBytes = fs.Read(buffer, 0, buffer.Length);
                            zipStream.Write(buffer, 0, sourceBytes);
                        } while (sourceBytes > 0);
                    }
                }
            }


            zipStream.Finish();
            zipStream.Close();

            Response.ContentType = "application/x-zip-compressed";
            Response.AppendHeader("Content-Disposition", "attachment; filename=SS.zip");
            Response.WriteFile(zipFilePath);
            Response.End();

        }

Response.Buffer = true;
  Response.Clear();
  Response.ClearContent();
  Response.ClearHeaders();

Response.Flush()
Response.Close()

Response.Buffer = true;
Response.Clear();
Response.ClearContent();
Response.ClearHeaders();
Response.ContentType = "application/x-zip-compressed";
Response.AppendHeader("Content-Disposition", "attachment; filename=SS.zip");
Response.WriteFile(zipFilePath);
Response.Flush()
Response.Close()
Response.End();