TransactionScope 报错

程序不加 TransactionScope 不会报错，加上后报 获取失败！错误消息：试图加载格式不正确的程序。 (异常来自 HRESULT:0x8007000B) 

    [Description("新建员工")]
    [WebInvoke(UriTemplate = "NewStaff", Method = "POST", ResponseFormat = WebMessageFormat.Json)]
    public M_Result<bool> NewStaff(TB_STAFF data)
    {
        M_Result<bool> reult = new M_Result<bool>() { ResultCode = (int)M_Enum.返回结果码.失败 };
        using (TransactionScope scope = new TransactionScope())
        {
            try
            {
                bll_staff.Update(data);
                reult.ResultCode = (int)M_Enum.返回结果码.成功;
                scope.Complete();
            }
            catch (Exception ex)
            {

                WriteLOG.WriteLog("user/NewStaff:" + ex.Message, 1);
                WriteLOG.WriteLog(ex.Message, 1);
                reult.ResultCode = (int)M_Enum.返回结果码.失败;
                reult.ResultMsg = "获取失败！错误消息：" + ex.Message;

            }
            finally
            {
                scope.Dispose();

            }
            return reult;
        }

    }

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