PowerBI Desktop is unable to open reports (April update?)

[Alexei]

I'm working on a report and yesterday PowerBI stopped opening it (while it did a week ago). There is the strange error message: "Object reference not set to an instance of an object" - it explains nothing, as any error message in PBI. It also provides "Copy details" button - these details listed below. Then, PBI starts doing something (no I/O, just dispatching memory up to 2Gb), and can be terminated via Task Manager only. The same effect on all previous versions of the same PBI report. Some other reports can be opened. 

Feedback Type:
Frown (Error)

Error Message:
Object reference not set to an instance of an object.

Stack Trace:
at Microsoft.PowerBI.Client.Windows.AnalysisServices.AnalysisServicesLoadContextFactory.CreateLoadToModelQueryEvaluatorFactory()
at Microsoft.PowerBI.Client.Windows.AnalysisServices.AnalysisServicesLoadContextFactory.OnSqlCredentialsMessage(IMessageChannel channel, SqlCredentialsRequestMessage requestMessage)
at Microsoft.Mashup.Evaluator.MessageHandlers.TryDispatch(IMessageChannel channel, Message message)
at Microsoft.Mashup.Evaluator.ChannelMessenger.ChannelMessageHandlers.TryDispatch(IMessageChannel channel, Message message)
at Microsoft.Mashup.Evaluator.MessageHandlers.Dispatch(IMessageChannel channel, Message message)
at Microsoft.Mashup.Evaluator.ChannelMessenger.OnMessageWithUnknownChannel(IMessageChannel baseChannel, MessageWithUnknownChannel messageWithUnknownChannel)
at Microsoft.Mashup.Evaluator.MessageHandlers.TryDispatch(IMessageChannel channel, Message message)
at Microsoft.Mashup.Evaluator.ChannelMessenger.ChannelMessageHandlers.TryDispatch(IMessageChannel channel, Message message)
at Microsoft.Mashup.Evaluator.MessageHandlers.Dispatch(IMessageChannel channel, Message message)
at Microsoft.PowerBI.Client.Windows.AnalysisServices.AnalysisServicesLoadContextFactory.MessageDispatchWorker(NamedPipeServerStream inputPipeStream, NamedPipeServerStream outputPipeStream, IMessenger messenger)
at Microsoft.Mashup.Host.Document.ExceptionHandlerExtensions.HandleExceptions(IExceptionHandler exceptionHandler, Action action)

Stack Trace Message:
Object reference not set to an instance of an object.

Invocation Stack Trace:
at Microsoft.Mashup.Host.Document.ExceptionExtensions.GetCurrentInvocationStackTrace()
at Microsoft.Mashup.Client.UI.Shared.StackTraceInfo..ctor(String exceptionStackTrace, String invocationStackTrace, String exceptionMessage)
at Microsoft.PowerBI.Client.Windows.Telemetry.PowerBIUserFeedbackServices.GetStackTraceInfo(Exception e)
at Microsoft.PowerBI.Client.Windows.Telemetry.PowerBIUserFeedbackServices.ReportException(IWindowHandle activeWindow, IUIHost uiHost, FeedbackPackageInfo feedbackPackageInfo, Exception e, Boolean useGDICapture)
at Microsoft.Mashup.Client.UI.Shared.UnexpectedExceptionHandler.<>c__DisplayClass14_0.<HandleException>b__0()
at Microsoft.Mashup.Host.Document.SynchronizationContextExtensions.<>c__DisplayClass0_1.<SendAndMarshalExceptions>b__0(Object null)
at System.RuntimeMethodHandle.InvokeMethod(Object target, Object[] arguments, Signature sig, Boolean constructor)
at System.Reflection.RuntimeMethodInfo.UnsafeInvokeInternal(Object obj, Object[] parameters, Object[] arguments)
at System.Delegate.DynamicInvokeImpl(Object[] args)
at System.Windows.Forms.Control.InvokeMarshaledCallbackDo(ThreadMethodEntry tme)
at System.Windows.Forms.Control.InvokeMarshaledCallbackHelper(Object obj)
at System.Threading.ExecutionContext.RunInternal(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean preserveSyncCtx)
at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean preserveSyncCtx)
at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state)
at System.Windows.Forms.Control.InvokeMarshaledCallback(ThreadMethodEntry tme)
at System.Windows.Forms.Control.InvokeMarshaledCallbacks()
at System.Windows.Forms.Control.WndProc(Message& m)
at System.Windows.Forms.NativeWindow.Callback(IntPtr hWnd, Int32 msg, IntPtr wparam, IntPtr lparam)
at System.Windows.Forms.UnsafeNativeMethods.DispatchMessageW(MSG& msg)
at System.Windows.Forms.UnsafeNativeMethods.DispatchMessageW(MSG& msg)
at System.Windows.Forms.Application.ComponentManager.System.Windows.Forms.UnsafeNativeMethods.IMsoComponentManager.FPushMessageLoop(IntPtr dwComponentID, Int32 reason, Int32 pvLoopData)
at System.Windows.Forms.Application.ThreadContext.RunMessageLoopInner(Int32 reason, ApplicationContext context)
at System.Windows.Forms.Application.ThreadContext.RunMessageLoop(Int32 reason, ApplicationContext context)
at Microsoft.PowerBI.Client.Windows.Services.UIBlockingService.WaitOnUIThreadForTaskCompletion(Task task)
at Microsoft.PowerBI.Client.Windows.Services.UIBlockingService.BlockUIAndRun[T](Func`1 asyncMethod)
at Microsoft.PowerBI.Client.Windows.Services.FileManager.OpenFile(IPowerBIWindowService windowService, IPbixFile fileToOpen, Nullable`1 entryPoint)
at Microsoft.PowerBI.Client.Program.TryOpenOrCreateReport(IUIHost uiHost, ISplashScreen splashScreen, IFileManager fileManager, IFileHistoryManager fileHistoryManager, String filePath, FileType fileType)
at Microsoft.PowerBI.Client.Program.<>c__DisplayClass2_0.<Main>b__1()
at Microsoft.PowerBI.Client.Windows.IExceptionHandlerExtensions.<>c__DisplayClass3_0.<HandleExceptionsWithNestedTasks>b__0()
at Microsoft.Mashup.Host.Document.ExceptionHandlerExtensions.HandleExceptions(IExceptionHandler exceptionHandler, Action action)
at Microsoft.PowerBI.Client.Program.Main(String[] args)

PowerBINonFatalError:
{"AppName":"PBIDesktop","AppVersion":"2.80.5803.1061","ModuleName":"Microsoft.PowerBI.Client.Windows.dll","Component":"Microsoft.PowerBI.Client.Windows.AnalysisServices.AnalysisServicesLoadContextFactory","Error":"System.NullReferenceException","MethodDef":"CreateLoadToModelQueryEvaluatorFactory","ErrorOffset":"18"}

[v-qiuyu-msft]

Hi @Alexei, 

The issue could be caused by enabling the "Enhanced dataset metadata" preview feature in PBI Desktop and opening a report with a calculate table that references a Direct Query source. If this report was originally created in an older version of PBI Desktop, then you should be able to restore a backup of the report before it was upgraded to the new metadata format. 

Steps to restore the V1 version of the report:

1. Open PBI Desktop
2. Disable the "Store datasets using enhanced metadata format" preview feature at File > Options and settings > Options > Preview features
3. Close PBI Desktop
4. Find the backup file at C:\Users\<user>\AppData\Local\Microsoft\Power BI Desktop\TempSaves\Backup
1. The backup file will have the same name with a timestamp appended to the end
5. Copy the backup file to the Desktop or other location
6. Open the file
7. File > Save As

This will resave the original, unupgraded pbix file. As long as you keep the Preview feature off, it won't be upgraded, and you should not hit this issue.

Best Regards,
Qiuyun Yu

[Alexei]

Thank you, this solution works!