EventID 1006 MSExchangeFastSearch

A customer had an issue with Microsoft Exchange 2013 search not working.  Users received an error "Your search didn't return any results" in Outlook Web App.

 

This following error was generated in the Application Logs on the server.

 

Log Name:      Application
Source:        MSExchangeFastSearch
Date:          14/10/2016 1:10:14 PM
Event ID:      1006
Task Category: General
Level:         Warning
Keywords:      Classic
User:          N/A
Computer:      Exchange.domain.local
Description:
The FastFeeder component received a connection exception from FAST. Error details: System.ServiceModel.EndpointNotFoundException: Could not connect to net.tcp://localhost:3847/. The connection attempt lasted for a time span of 00:00:02.0469288. TCP error code 10061: No connection could be made because the target machine actively refused it 127.0.0.1:3847.  ---> System.Net.Sockets.SocketException: No connection could be made because the target machine actively refused it 127.0.0.1:3847
   at System.Net.Sockets.Socket.EndConnect(IAsyncResult asyncResult)
   at System.ServiceModel.Channels.SocketConnectionInitiator.ConnectAsyncResult.OnConnect(IAsyncResult result)
   --- End of inner exception stack trace ---

Server stack trace:
   at System.Runtime.AsyncResult.End[TAsyncResult](IAsyncResult result)
   at System.ServiceModel.Channels.CommunicationObject.EndOpen(IAsyncResult result)

Exception rethrown at [0]:
   at System.Runtime.Remoting.Proxies.RealProxy.HandleReturnMessage(IMessage reqMsg, IMessage retMsg)
   at System.Runtime.Remoting.Proxies.RealProxy.PrivateInvoke(MessageData& msgData, Int32 type)
   at System.ServiceModel.ICommunicationObject.EndOpen(IAsyncResult result)
   at Microsoft.Exchange.Search.OperatorSchema.PagingImsFlowExecutor.CreateProxy()
   at Microsoft.Exchange.Search.OperatorSchema.PagingImsFlowExecutor.AcquireProxy()
   at Microsoft.Exchange.Search.OperatorSchema.PagingImsFlowExecutor.ExecuteServiceCall(IProcessingEngineChannel& serviceProxy, Action`1 call, Int32 retryCount)
   at Microsoft.Exchange.Search.OperatorSchema.PagingImsFlowExecutor.ExecuteAndReadPage(QueryParameters parameters, String outputName)
   at Microsoft.Exchange.Search.OperatorSchema.PagingImsFlowExecutor.GetHitCount(QueryParameters parameters)
   at Microsoft.Exchange.Search.Fast.ExchangeQueryExecutor.<>c__DisplayClass20.b__1f()
   at Microsoft.Exchange.Search.Fast.ExchangeQueryExecutor.RunUnderExceptionHandler[T](Func`1 call, IDiagnosticsSession session, String flowName)

 

This issue occurs when the "Microsoft Exchange Search Host Controller" service is in a stopped state.  My customer installed the latest Cumulative Update for Exchange 2013 and after the installation finished, the Search Host Controller was not set back to an Automatic.