Asp.Net程序目录下文件夹或文件操作导致Session失效的解决方案

<system.web>
  <sessionstate mode="stateserver" stateconnectionstring="tcpip=127.0.0.1:42424" sqlconnectionstring="data 
  source=127.0.0.1;trusted_connection=yes" cookieless="false" timeout="40"/>
</system.web>

void application_start(object sender, eventargs e)
  {
    // 在应用程序启动时运行的代码
    try
    {
      //启动asp.net 状态服务
      string g_servicename = "aspnet_state";
      system.serviceprocess.servicecontroller[] servicecontrollers = 
        system.serviceprocess.servicecontroller.getservices();
      foreach (system.serviceprocess.servicecontroller service in servicecontrollers)
      {
        if (service.servicename == g_servicename)
        {
          if (service != null && service.status != system.serviceprocess.servicecontrollerstatus.running)
          {
            service.start();
　　　　　　　　　　　　　　 simpleloghelper.writeerror(g_servicename + "服务已开启");
          }
          else
          {
            if (service == null)
            {
              simpleloghelper.writeerror(g_servicename + "服务未安装");
            }
            else
            {
              simpleloghelper.writeerror(g_servicename + "服务正在运行...");
            }
          }
          break;
        }
      }
    }
    catch (exception ex)
    {
      simpleloghelper.writeerror(ex.tostring());
    }
  }