客户版本3.0，打了2014年11月21日补丁。
偶然情况下流程会报错挂起，如下图：
错误信息：
Connection Timeout Expired. The timeout period elapsed while attempting to consume the pre-login handshake acknowledgement. This could be because the pre-login handshake failed or the server was unable to respond back in time. The duration spent while attempting to connect to this server was - [Pre-Login] initialization=0; handshake=14998;
错误堆栈：
Kingdee.BOS.KDExceptionDatabase: Connection Timeout Expired. The timeout period elapsed while attempting to consume the pre-login handshake acknowledgement. This could be because the pre-login handshake failed or the server was unable to respond back in time. The duration spent while attempting to connect to this server was - [Pre-Login] initialization=0; handshake=14998;
Server stack trace:
在 Kingdee.BOS.App.Data.AbstractDatabase.ExecuteNonQuery(DbCommand command, IEnumerable`1 listParam)
在 Kingdee.BOS.App.Data.DBUtils.ExecuteBatch(Context ctx, List`1 lstSqlObj)
在 Kingdee.BOS.App.LogService.Log.DoWriteLog(Context ctx, List`1 logObjects)
在 Kingdee.BOS.App.Core.Messages.XunTong.MessageService.Send(XunTongMessage message, List`1 users, String sPubAcctCode, String sPubAcctKey)
在 Kingdee.BOS.App.Core.Messages.XunTongService.SendMessage(Context ctx, XunTongMessage message, List`1 users)
Exception rethrown at [0]:
在 System.Runtime.Remoting.Proxies.RealProxy.HandleReturnMessage(IMessage reqMsg, IMessage retMsg)
在 System.Runtime.Remoting.Proxies.RealProxy.PrivateInvoke(MessageData& msgData, Int32 type)
在 Kingdee.BOS.Contracts.Messages.IXunTongService.SendMessage(Context ctx, XunTongMessage message, List`1 users)
在 Kingdee.BOS.Workflow.App.Core.Repositories.XunTongRepository.DoSendAssignmentMessage(Context ctx, BusinessInfo businessInfo, BOSDynamicRow bOSDynamicRow, Assign assign)
在 Kingdee.BOS.Workflow.ActionEvents.ApprovalAction.Execute(ActionEventContext ctx)
在 Kingdee.BOS.Workflow.Elements.ActionEvent.ExecuteActionEvent(ActionEventContext ctx)
在 Kingdee.BOS.Workflow.Kernel.Runtime.MapStateExecutor.ExecuteActionEvents()
在 Kingdee.BOS.Workflow.Kernel.Runtime.MapSchedular.ExecuteMapStateInstance(IMapStateInstance instance)
在 Kingdee.BOS.Workflow.Kernel.Runtime.MapSchedular.Run()
请总部老师帮忙分析一下看看， 平时客户使用网络也还算稳定，不会出现突然断掉或者其他异常情况。
谢谢！
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