事务日志里发现K3Cloud频繁的出错（执行计划执行出错）

K3Cloud服务器事务日志一直报这个错，是什么原因，怎么解决？？

执行计划执行出错, 帐套Id:90b11c363d63abf511e37144be9c7bfa 帐套名称: 路达集团云平台, 执行计划Id:00155d594c31824e11e4072ac52fe426, 执行时间:2014-12-22 07:55:43,
System.Net.WebException: Unable to connect to the remote server ---> System.Net.Sockets.SocketException: 由于目标计算机积极拒绝，无法连接。 127.0.0.1:80
at System.Net.Sockets.Socket.DoConnect(EndPoint endPointSnapshot, SocketAddress socketAddress)
at System.Net.ServicePoint.ConnectSocketInternal(Boolean connectFailure, Socket s4, Socket s6, Socket& socket, IPAddress& address, ConnectSocketState state, IAsyncResult asyncResult, Exception& exception)
--- End of inner exception stack trace ---
at System.Net.HttpWebRequest.GetRequestStream(TransportContext& context)
at System.Net.HttpWebRequest.GetRequestStream()
at Kingdee.BOS.ServiceFacade.KDServiceClient.KDServiceClient.DoPost(String uri, MessageFormats format, ParaDictionary txtParams)
at Kingdee.BOS.ServiceFacade.KDServiceClient.KDServiceClient.doExecute[T](KDBaseRequest request)
at Kingdee.BOS.ServiceFacade.KDServiceClient.BaseServiceProxy.ExecuteService[T](String method, Object[] args)
at Kingdee.BOS.Schedule.Core.BackgroundJob.DoTask(Object scheduleObj)