你好！
现在的环境是exchange server 2013 CU20 ，在exchange后端服务器上有个事件ID 1012报错信息。请问这个报错信息是怎么引起的？改如何处理？请你详细描述关于此报错信息解决方案。
相关报错信息：
Exchange Server Information Store has encountered an error while executing a full-text index query ("and(subject:string("SearchQueryStxProbe*", mode="and"), folderid:string("9CA0C9488A1E7C45B0F6E3FAE6CDF07C00000000010C0000"))").
Error information: System.TimeoutException: Failed to open a channel.
在 Microsoft.Exchange.Search.OperatorSchema.PagingImsFlowExecutor.ExecuteServiceCall(IProcessingEngineChannel& serviceProxy, Action`1 call, Int32 retryCount)
在 Microsoft.Exchange.Search.OperatorSchema.PagingImsFlowExecutor.ExecuteSearchFlow(String flowName, Dictionary`2 inputData)
在 Microsoft.Exchange.Search.OperatorSchema.PagingImsFlowExecutor.<ExecuteInternal>d__23.MoveNext()
在 Microsoft.Exchange.Search.OperatorSchema.PagingImsFlowExecutor.<ExecuteSimple>d__a.MoveNext()
在 Microsoft.Exchange.Server.Storage.FullTextIndex.FullTextIndexQuery.ExecutePagedFullTextIndexQuery(Guid databaseGuid, Guid mailboxGuid, Int32 mailboxNumber, String query, CultureInfo culture, Guid correlationId, Boolean needConversationId, QueryLoggingContext
loggingContext, PagedQueryResults pagedQueryResults)
在 Microsoft.Exchange.Server.Storage.StoreCommonServices.StoreFullTextIndexQuery.ExecuteOnePage(Context context, MailboxState mailboxState, Boolean needConversationDocumentId, SearchExecutionDiagnostics diagnostics)
