C# 用UploadFile上传文件，保存到服务器中，但是在测试区正常，在正式去报错

    测试区的web.config没有配置requestLengthDiskThreshold，正式区好像也没有，但是在
    正式区上传附件报“Cannot access a closed file”，请问怎么解决？





    if (fupFile.PostedFile != null && fupFile.PostedFile.ContentLength > 0)
    {
        if (fupFile.HasFile)
        {

            ListItem item = new ListItem();
            item.Value = item.Text = fupFile.PostedFile.FileName;
            if (!lbxFile.Items.Contains(item))
            {
                lbxFile.Items.Add(item);
                files.Add(fupFile);
            }

        }
        if (files.Count > 0)
        {
            string WF_NO;
            string WF_Sale;
            string filename = "";
            string path = "d:\\Lorom\\ProductCenter\\WorkFlow\\FTPFile\\" + Session["wf_sale"].ToString() + "\\" + Session["WF_NO"].ToString() + "\\";
            if (!Directory.Exists(path))
            {
                Directory.CreateDirectory(path);
            }
            lblShow.Text = fupFile.PostedFile.FileName;

            WF_Sale = Session["UserNO"].ToString();
            WF_NO = Session["WF_NO"].ToString();


            WCFHelperBase wcfBase = new WCFHelperBase();
            foreach (FileUpload fup in files)
            {
                if (fup.HasFile)

                    filename = fup.FileName;
                //string extend = Path.GetExtension(filename);

                // fupFile.PostedFile.SaveAs(Server.MapPath(path)+"\\"+filename);
                // Directory.CreateDirectory(path);
                //myFile.SaveAs(path + fupFile);
                wcfBase.csHelper.GetUnsignFile(WF_NO, filename, WF_Sale);
                fup.SaveAs(path + "/" + fup.FileName);//无法访问已关闭的文件

            }
            //Page.ClientScript.RegisterClientScriptBlock(typeof(string), "", @"<script>alert('上传成功！')</script>");
            wcfBase.CloseWCF();
            Response.AddHeader("Refresh", "0");
        }
    }