When a report has no layout (typically if you create a report with a Word layout and you miss to set DefaultLayout = Word), then BC online returns a generic error page telling that an error occured...

On-premise, the Windows event log gives a bit more info (see below).
Could you improve the error message in the client so it can also be understandable in BC online?


Windows event log:

Tenant ID:
Environment Name:
Environment Type:
User:
Type: System.ArgumentNullException
Message:
Value cannot be null.
Parameter name: reportLayout
ParamName: reportLayout
StackTrace:
at Microsoft.Dynamics.Nav.Types.Report.Runtime.LocalReportHandle..ctor(Int32 reportId, Byte[] reportLayout, Boolean enableExternalImages, Boolean enableHyperlinks, Boolean enableExternalAssemblies, Boolean enableReportViewerInternalAppDomainIsolation, Boolean enableAppDomainMonitor)
at Microsoft.Dynamics.Nav.Runtime.NavSession.<>c__DisplayClass190_0.b__0(MetaReport metaReport)
at Microsoft.Dynamics.Nav.Runtime.LocalReportCache.GetLocalReport(MetaReport metaReport)
at Microsoft.Dynamics.Nav.Runtime.NavReport.EffectiveLocalReportHandle()
at Microsoft.Dynamics.Nav.Runtime.ReportSaveAsRenderer.Start()
at Microsoft.Dynamics.Nav.Runtime.DataItemIterator.b__64_0()
at Microsoft.Dynamics.Nav.Runtime.DataItemIterator.ExecuteDataItemIterator(NavSqlConnectionIntent connectionIntent)
at Microsoft.Dynamics.Nav.Runtime.NavReport.<>c__DisplayClass154_0.b__0()
at Microsoft.Dynamics.Nav.Runtime.ApplicationObjectRootScope.AddApplicationObjectRootScope[T](NavApplicationObjectBase applicationObject, Func`1 action)
at Microsoft.Dynamics.Nav.Runtime.NavReport.RunReportInternal(NavRecord record, Boolean displayResult, ReportRunOptions reportRunOptions, Nullable`1 formResult)
at Microsoft.Dynamics.Nav.Runtime.NavReport.RunReport(NavRecord record, ReportRunOptions reportRunOptions, Nullable`1 formResult)
at Microsoft.Dynamics.Nav.Runtime.NavReport.RunReport(Nullable`1 requestWindow, Nullable`1 systemPrinter, NavRecord record, ReportRunMode mode, String printerName)
at Microsoft.Dynamics.Nav.Runtime.NavReport.RunReport(Int32 reportId, Nullable`1 requestWindow, Nullable`1 systemPrinter, NavRecord record, ReportRunMode runMode)
at Microsoft.Dynamics.Nav.Runtime.NavReport.Run(Int32 reportId)
at Microsoft.Dynamics.Nav.Service.NSService.RunReport(ApplicationMethodRequest applicationMethodRequest)
at SyncInvokeRunReport(Object , Object[] , Object[] )
at System.ServiceModel.Dispatcher.SyncMethodInvoker.Invoke(Object instance, Object[] inputs, Object[]& outputs)
at Microsoft.Dynamics.Nav.Service.ServiceOperationInvoker.RunInTransactionCombinator(ServiceOperation innerOperation, NSServiceBase serviceInstance, MethodBase syncMethod, Object[] inputs, Object[]& outputs)
at Microsoft.Dynamics.Nav.Service.ServiceOperationInvoker.<>c__DisplayClass28_1.b__1(NSServiceBase serviceInstance, Object[] inputs, Object[]& outputs)
at Microsoft.Dynamics.Nav.Service.ServiceOperationInvoker.TransientErrorRetryCombinator(ServiceOperation innerOperation, NSServiceBase serviceInstance, MethodBase syncMethod, Object[] inputs, Object[]& outputs)
at Microsoft.Dynamics.Nav.Service.ServiceOperationInvoker.<>c__DisplayClass28_1.b__1(NSServiceBase serviceInstance, Object[] inputs, Object[]& outputs)
at Microsoft.Dynamics.Nav.Service.ServiceOperationInvoker.ErrorMappingCombinator(ServiceOperation innerOperation, NSServiceBase serviceInstance, MethodBase syncMethod, Object[] inputs, Object[]& outputs)
Source: Microsoft.Dynamics.Nav.Types.Report.Runtime
HResult: -2147467261
StackTrace:
at Microsoft.Dynamics.Nav.Types.Report.Runtime.LocalReportHandle..ctor(Int32 reportId, Byte[] reportLayout, Boolean enableExternalImages, Boolean enableHyperlinks, Boolean enableExternalAssemblies, Boolean enableReportViewerInternalAppDomainIsolation, Boolean enableAppDomainMonitor)
at Microsoft.Dynamics.Nav.Runtime.NavSession.<>c__DisplayClass190_0.b__0(MetaReport metaReport)
at Microsoft.Dynamics.Nav.Runtime.LocalReportCache.GetLocalReport(MetaReport metaReport)
at Microsoft.Dynamics.Nav.Runtime.NavReport.EffectiveLocalReportHandle()
at Microsoft.Dynamics.Nav.Runtime.ReportSaveAsRenderer.Start()
at Microsoft.Dynamics.Nav.Runtime.DataItemIterator.b__64_0()
at Microsoft.Dynamics.Nav.Runtime.DataItemIterator.ExecuteDataItemIterator(NavSqlConnectionIntent connectionIntent)
at Microsoft.Dynamics.Nav.Runtime.NavReport.<>c__DisplayClass154_0.b__0()
at Microsoft.Dynamics.Nav.Runtime.ApplicationObjectRootScope.AddApplicationObjectRootScope[T](NavApplicationObjectBase applicationObject, Func`1 action)
at Microsoft.Dynamics.Nav.Runtime.NavReport.RunReportInternal(NavRecord record, Boolean displayResult, ReportRunOptions reportRunOptions, Nullable`1 formResult)
at Microsoft.Dynamics.Nav.Runtime.NavReport.RunReport(NavRecord record, ReportRunOptions reportRunOptions, Nullable`1 formResult)
at Microsoft.Dynamics.Nav.Runtime.NavReport.RunReport(Nullable`1 requestWindow, Nullable`1 systemPrinter, NavRecord record, ReportRunMode mode, String printerName)
at Microsoft.Dynamics.Nav.Runtime.NavReport.RunReport(Int32 reportId, Nullable`1 requestWindow, Nullable`1 systemPrinter, NavRecord record, ReportRunMode runMode)
at Microsoft.Dynamics.Nav.Runtime.NavReport.Run(Int32 reportId)
at Microsoft.Dynamics.Nav.Service.NSService.RunReport(ApplicationMethodRequest applicationMethodRequest)
at SyncInvokeRunReport(Object , Object[] , Object[] )
at System.ServiceModel.Dispatcher.SyncMethodInvoker.Invoke(Object instance, Object[] inputs, Object[]& outputs)
at Microsoft.Dynamics.Nav.Service.ServiceOperationInvoker.RunInTransactionCombinator(ServiceOperation innerOperation, NSServiceBase serviceInstance, MethodBase syncMethod, Object[] inputs, Object[]& outputs)
at Microsoft.Dynamics.Nav.Service.ServiceOperationInvoker.<>c__DisplayClass28_1.b__1(NSServiceBase serviceInstance, Object[] inputs, Object[]& outputs)
at Microsoft.Dynamics.Nav.Service.ServiceOperationInvoker.TransientErrorRetryCombinator(ServiceOperation innerOperation, NSServiceBase serviceInstance, MethodBase syncMethod, Object[] inputs, Object[]& outputs)
at Microsoft.Dynamics.Nav.Service.ServiceOperationInvoker.<>c__DisplayClass28_1.b__1(NSServiceBase serviceInstance, Object[] inputs, Object[]& outputs)
at Microsoft.Dynamics.Nav.Service.ServiceOperationInvoker.ErrorMappingCombinator(ServiceOperation innerOperation, NSServiceBase serviceInstance, MethodBase syncMethod, Object[] inputs, Object[]& outputs)