Question

System.AggregateException: One or more errors occurred. (Object reference not set to an instance of an object.)

0

I am getting this error. Everything is running fine locally, so i commit all the changes to the repository. But when I am running again the app locally, i faced this error. Any solution? System.AggregateException: One or more errors occurred. (Object reference not set to an instance of an object.) ---> System.NullReferenceException: Object reference not set to an instance of an object. at Mendix.Modeler.WebUI.Forms.Exporter.ExportContext.GetExportID(IDocumentObject documentObject, String subcomponentName) in Mendix.Modeler.WebUI\Forms\Exporter\ExportContext.cs:line 100 at Mendix.Modeler.WebUI.Forms.Widgets.CustomWidgets.CustomWidget.AddWidgetObjectProperties[TBuilder](WidgetObject widgetObject, TBuilder builder, IExportContext context, Boolean isNative) in Mendix.Modeler.WebUI\Forms\Widgets\CustomWidgets\CustomWidget.cs:line 514 at Mendix.Modeler.WebUI.Forms.Widgets.CustomWidgets.CustomWidget.Mendix.Modeler.WebUI.PluginWidgets.Export.IExportAsPluginWidget.CreatePluginWidget(IExportContext context, IWidgetContainer widgetContainer) in Mendix.Modeler.WebUI\Forms\Widgets\CustomWidgets\CustomWidget.cs:line 372 at Mendix.Modeler.WebUI.PluginWidgets.PluginWidgetUtil.ToPluginWidget(IExportContext context, IWidgetContainer widgetContainer, IWidget widget) in Mendix.Modeler.WebUI\PluginWidgets\PluginWidgetUtil.cs:line 27 at System.Linq.Enumerable.SelectIListIterator`2.MoveNext() at System.Linq.Enumerable.WhereEnumerableIterator`1.MoveNext() at Mendix.Common.Util.EnumerableUtil.ForEach[T](IEnumerable`1 source, Action`1 action) in Mendix.Common\Util\EnumerableUtil.cs:line 50 at Mendix.Modeler.WebUI.PluginWidgets.Builder.PropertyContainerBuilder`1.WithWidgetsProperty(String key, Func`2 builder, EntityIdentifier entityId, SnippetCall snippetCall) in Mendix.Modeler.WebUI\PluginWidgets\Builder\PropertyContainerBuilder.cs:line 206 at Mendix.Modeler.WebUI.Forms.Widgets.EntityWidgets.DataViews.DataView.Mendix.Modeler.WebUI.PluginWidgets.Export.IExportAsPluginWidget.CreatePluginWidget(IExportContext context, IWidgetContainer widgetContainer) in Mendix.Modeler.WebUI\Forms\Widgets\EntityWidgets\DataViews\DataView.cs:line 0 at Mendix.Modeler.WebUI.PluginWidgets.PluginWidgetUtil.ToPluginWidget(IExportContext context, IWidgetContainer widgetContainer, IWidget widget) in Mendix.Modeler.WebUI\PluginWidgets\PluginWidgetUtil.cs:line 27 at System.Linq.Enumerable.SelectIListIterator`2.MoveNext() at System.Linq.Enumerable.WhereEnumerableIterator`1.MoveNext() at Mendix.Common.Util.EnumerableUtil.ForEach[T](IEnumerable`1 source, Action`1 action) in Mendix.Common\Util\EnumerableUtil.cs:line 50 at Mendix.Modeler.WebUI.PluginWidgets.Builder.PropertyContainerBuilder`1.WithWidgetsProperty(String key, Func`2 builder, EntityIdentifier entityId, SnippetCall snippetCall) in Mendix.Modeler.WebUI\PluginWidgets\Builder\PropertyContainerBuilder.cs:line 206 at Mendix.Modeler.WebUI.Forms.Widgets.LayoutGrids.LayoutGrid.<>c__DisplayClass11_3.<Mendix.Modeler.WebUI.PluginWidgets.Export.IExportAsPluginWidget.CreatePluginWidget>b__3(LayoutGridColumn col, Int32 colIndex) in Mendix.Modeler.WebUI\Forms\Widgets\LayoutGrids\LayoutGrid.cs:line 119 at System.Linq.Enumerable.SelectIterator[TSource,TResult](IEnumerable`1 source, Func`3 selector)+MoveNext() at Mendix.Common.Util.EnumerableUtil.ForEach[T](IEnumerable`1 source, Action`1 action) in Mendix.Common\Util\EnumerableUtil.cs:line 50 at Mendix.Modeler.WebUI.PluginWidgets.Builder.PropertyContainerBuilder`1.WithWidgetsProperty(String key, Func`2 builder, EntityIdentifier entityId, SnippetCall snippetCall) in Mendix.Modeler.WebUI\PluginWidgets\Builder\PropertyContainerBuilder.cs:line 206 at Mendix.Modeler.WebUI.Forms.Widgets.LayoutGrids.LayoutGrid.<>c__DisplayClass11_1.<Mendix.Modeler.WebUI.PluginWidgets.Export.IExportAsPluginWidget.CreatePluginWidget>b__1(LayoutGridRow row, Int32 rowIndex) in Mendix.Modeler.WebUI\Forms\Widgets\LayoutGrids\LayoutGrid.cs:line 113 at System.Linq.Enumerable.SelectIterator[TSource,TResult](IEnumerable`1 source, Func`3 selector)+MoveNext() at Mendix.Common.Util.EnumerableUtil.ForEach[T](IEnumerable`1 source, Action`1 action) in Mendix.Common\Util\EnumerableUtil.cs:line 50 at Mendix.Modeler.WebUI.PluginWidgets.Builder.PropertyContainerBuilder`1.WithWidgetsProperty(String key, Func`2 builder, EntityIdentifier entityId, SnippetCall snippetCall) in Mendix.Modeler.WebUI\PluginWidgets\Builder\PropertyContainerBuilder.cs:line 206 at Mendix.Modeler.WebUI.Forms.Widgets.LayoutGrids.LayoutGrid.Mendix.Modeler.WebUI.PluginWidgets.Export.IExportAsPluginWidget.CreatePluginWidget(IExportContext context, IWidgetContainer widgetContainer) in Mendix.Modeler.WebUI\Forms\Widgets\LayoutGrids\LayoutGrid.cs:line 109 at Mendix.Modeler.WebUI.Forms.Exporter.FormWriter.WriteWidget(IWriteWidget widget, IWebExportContext context) in Mendix.Modeler.WebUI\Forms\Exporter\FormWriter.cs:line 101 at Mendix.Modeler.WebUI.Forms.Exporter.FormWriter.WriteArgument(String parameterName, IEnumerable`1 widgets) in Mendix.Modeler.WebUI\Forms\Exporter\FormWriter.cs:line 82 at Mendix.Modeler.WebUI.Forms.Exporter.FormWriter.WriteArguments(IDictionary`2 arguments) in Mendix.Modeler.WebUI\Forms\Exporter\FormWriter.cs:line 295 at Mendix.Modeler.WebUI.Forms.Exporter.FormWriter.<>c__DisplayClass23_0.<Write>b__0() in Mendix.Modeler.WebUI\Forms\Exporter\FormWriter.cs:line 191 at Mendix.Modeler.Common.ResolveCache.TrackResolves(Action code) in Mendix.Modeler.Core\Common\Problems\ResolveCache.cs:line 100 at Mendix.Modeler.WebUI.Forms.Exporter.FormWriter.Write() in Mendix.Modeler.WebUI\Forms\Exporter\FormWriter.cs:line 196 at Mendix.Modeler.Common.ResolveCache.TrackResolves(Action code) in Mendix.Modeler.Core\Common\Problems\ResolveCache.cs:line 100 at Mendix.Modeler.WebUI.Forms.Exporter.FormExporter.<>c__DisplayClass5_1.<ExportForms>b__2() in Mendix.Modeler.WebUI\Forms\Exporter\FormExporter.cs:line 91 at Mendix.Modeler.Common.ResolveCache.WithCache[T](IProject project, Func`1 action) in Mendix.Modeler.Core\Common\Problems\ResolveCache.cs:line 73 at Mendix.Modeler.WebUI.Forms.Exporter.FormExporter.<>c__DisplayClass5_0.<ExportForms>b__1(IDocument document) in Mendix.Modeler.WebUI\Forms\Exporter\FormExporter.cs:line 81 at Mendix.Modeler.Projects.Changes.ChangedDocumentsProcessor`1.<>c__DisplayClass6_0.<ProcessChangedDocuments>g__DoProcess|2(IDocument document) in Mendix.Modeler.Core\Projects\Changes\ChangedDocumentsProcessor.cs:line 90 at System.Linq.Parallel.ForAllOperator`1.ForAllEnumerator`1.MoveNext(TInput& currentElement, Int32& currentKey) at System.Linq.Parallel.ForAllSpoolingTask`2.SpoolingWork() at System.Linq.Parallel.SpoolingTaskBase.Work() at System.Linq.Parallel.QueryTask.BaseWork(Object unused) at System.Threading.ExecutionContext.RunFromThreadPoolDispatchLoop(Thread threadPoolThread, ExecutionContext executionContext, ContextCallback callback, Object state)--- End of stack trace from previous location --- at System.Threading.Tasks.Task.ExecuteWithThreadLocal(Task& currentTaskSlot, Thread threadPoolThread) --- End of inner exception stack trace --- at System.Linq.Parallel.QueryTaskGroupState.QueryEnd(Boolean userInitiatedDispose) at System.Linq.Parallel.SpoolingTask.SpoolForAll[TInputOutput,TIgnoreKey](QueryTaskGroupState groupState, PartitionedStream`2 partitions, TaskScheduler taskScheduler) at System.Linq.Parallel.MergeExecutor`1.Execute[TKey](PartitionedStream`2 partitions, Boolean ignoreOutput, ParallelMergeOptions options, TaskScheduler taskScheduler, Boolean isOrdered, CancellationState cancellationState, Int32 queryId) at System.Linq.Parallel.PartitionedStreamMerger`1.Receive[TKey](PartitionedStream`2 partitionedStream) at System.Linq.Parallel.ForAllOperator`1.WrapPartitionedStream[TKey](PartitionedStream`2 inputStream, IPartitionedStreamRecipient`1 recipient, Boolean preferStriping, QuerySettings settings) at System.Linq.Parallel.UnaryQueryOperator`2.UnaryQueryOperatorResults.ChildResultsRecipient.Receive[TKey](PartitionedStream`2 inputStream) at System.Linq.Parallel.ScanQueryOperator`1.ScanEnumerableQueryOperatorResults.GivePartitionedStream(IPartitionedStreamRecipient`1 recipient) at System.Linq.Parallel.UnaryQueryOperator`2.UnaryQueryOperatorResults.GivePartitionedStream(IPartitionedStreamRecipient`1 recipient) at System.Linq.Parallel.QueryOperator`1.GetOpenedEnumerator(Nullable`1 mergeOptions, Boolean suppressOrder, Boolean forEffect, QuerySettings querySettings) at System.Linq.Parallel.ForAllOperator`1.RunSynchronously() at System.Linq.ParallelEnumerable.ForAll[TSource](ParallelQuery`1 source, Action`1 action) at Mendix.Modeler.Projects.Changes.ChangedDocumentsProcessor`1.ProcessChangedDocuments(IProject project, ProjectChanges projectChanges, Func`2 processDocument) in Mendix.Modeler.Core\Projects\Changes\ChangedDocumentsProcessor.cs:line 82 at Mendix.Modeler.WebUI.Forms.Exporter.FormExporter.ExportForms(IProject project, Boolean updateRunningProject) in Mendix.Modeler.WebUI\Forms\Exporter\FormExporter.cs:line 62 at Mendix.Modeler.WebUI.Deployment.WebUIDeploymentWorker.ExportPages(IProject project, IProgressInfo info, Boolean updateRunningProject) in Mendix.Modeler.WebUI\Deployment\WebUIDeploymentWorker.cs:line 209 at Mendix.Modeler.WebUI.Deployment.WebUIDeploymentWorker.DoWork(DeploymentPhase phase, IProject project, DeploymentSettings settings, IProgressInfo info) in Mendix.Modeler.WebUI\Deployment\WebUIDeploymentWorker.cs:line 109 at Mendix.Modeler.Deployment.DeploymentProcessBuilder.ExecuteDeploymentWorkForPhase(DeploymentPhase phase, IProject project, DeploymentSettings settings, IProgressInfo info) in Mendix.Modeler.Deployment\DeploymentProcessBuilder.cs:line 185 at Mendix.Modeler.Deployment.DeploymentProcessBuilder.<>c__DisplayClass13_1.<AddBuildStepWithOverride>b__2() in Mendix.Modeler.Deployment\DeploymentProcessBuilder.cs:line 155 at Mendix.Modeler.Projects.ProjectStructureManager.<>c__DisplayClass2_0.<DoWithOverride>b__0() in Mendix.Modeler.Core\Projects\ProjectStructureManager.cs:line 40 at Mendix.Modeler.Projects.ProjectStructureManager.Do[T](IProject projectOverride, Func`1 action) in Mendix.Modeler.Core\Projects\ProjectStructureManager.cs:line 60 at Mendix.Modeler.Projects.ProjectStructureManager.DoWithOverride(IProject projectOverride, Action action) in Mendix.Modeler.Core\Projects\ProjectStructureManager.cs:line 38 at Mendix.Modeler.Deployment.DeploymentProcessBuilder.<>c__DisplayClass13_1.<AddBuildStepWithOverride>b__1() in Mendix.Modeler.Deployment\DeploymentProcessBuilder.cs:line 154 at Mendix.Modeler.ProtectedModules.ProtectedModulesUnlocker.<>c__DisplayClass3_0.<Do>b__0() in Mendix.Modeler.Core\ProtectedModules\ProtectedModulesUnlocker.cs:line 22 at Mendix.Modeler.ProtectedModules.ProtectedModulesUnlocker.ExecuteInContext[T](Boolean unlockImplementation, Func`1 code) in Mendix.Modeler.Core\ProtectedModules\ProtectedModulesUnlocker.cs:line 42 at Mendix.Modeler.ProtectedModules.ProtectedModulesUnlocker.Do(Boolean unlockImplementation, Action action) in Mendix.Modeler.Core\ProtectedModules\ProtectedModulesUnlocker.cs:line 20 at Mendix.Modeler.Deployment.DeploymentProcessBuilder.<>c__DisplayClass13_0.<AddBuildStepWithOverride>b__0(IProgressInfo info) in Mendix.Modeler.Deployment\DeploymentProcessBuilder.cs:line 153 at Mendix.Modeler.Deployment.FileIOExceptionHandlingProcess.<>c__DisplayClass2_1.<AddStep>b__1() in Mendix.Modeler.Deployment\FileIOExceptionHandlingProcess.cs:line 22 at Mendix.Modeler.Deployment.FileIOExceptionHandlingProcess.CatchDiskException(Action action) in Mendix.Modeler.Deployment\FileIOExceptionHandlingProcess.cs:line 31 at Mendix.Modeler.Deployment.FileIOExceptionHandlingProcess.<>c__DisplayClass2_0.<AddStep>b__0(IProgressInfo info) in Mendix.Modeler.Deployment\FileIOExceptionHandlingProcess.cs:line 22 at Mendix.Modeler.Utility.Progress.StepBase`1.Run(TProgressInfo info) in Mendix.Modeler.Utility\Progress\Step.cs:line 31 at Mendix.Modeler.Utility.Progress.StepBase`1.Mendix.Modeler.Utility.Progress.IStep.Run(Object progressInfo) in Mendix.Modeler.Utility\Progress\Step.cs:line 36 at Mendix.Modeler.UIFramework.Progress.ProcessRunner.RunStep(IStep step) in Mendix.Modeler.UIFramework\Progress\ProcessRunner.cs:line 170 at Mendix.Modeler.UIFramework.Progress.ProcessRunner.OnDoWork(Object sender, DoWorkEventArgs e) in Mendix.Modeler.UIFramework\Progress\ProcessRunner.cs:line 81 at System.ComponentModel.BackgroundWorker.OnDoWork(DoWorkEventArgs e) at System.ComponentModel.BackgroundWorker.WorkerThreadStart(Object argument)--- End of stack trace from previous location --- at Mendix.Modeler.UIFramework.Progress.ProcessRunner.Run() in Mendix.Modeler.UIFramework\Progress\ProcessRunner.cs:line 57 at Mendix.Modeler.Deployment.Deployer.RunProcess(IProcess process, String what, Boolean isPackage) in Mendix.Modeler.Deployment\Deployer.cs:line 89

asked 2025-02-19

Babylyn Lao ay

2 answers

Syman Scholze · Answer 1 · 2025-04-08

Hi I got a very similar error and managed to solve it by the following procedure:

Remove a page from the app
Try starting the app
1. If it doesn't start, readd the page and delete another one
2. If the app starts, readd the page and proceed with 3
On the page in question remove a widget
Try starting the app
1. If it doesn't start, readd the widget and delete another one
2. If the app starts, readd the widget and proceed with 5
Take a look to all attributes of the widgets, also styles and dynamic classes

In my case I found out that the Label of one widget was referencing an attribute which didn't exist anymore. After I fixed that error the NULL-reference error was gone and I managed to start my app.

Peter Delrue · Answer 2 · 2025-08-01

I got this error immediatly after creating a new app, without adding anything extra. Bug in Mendix 11?

UPDATE : This was in Mendix 11.0.0 Beta2. I updated to Mendix 11.1.0 and everything is OK now.

System.AggregateException: One or more errors occurred. (Object reference not set to an instance of an object.) ---> System.NullReferenceException: Object reference not set to an instance of an object. at Mendix.Modeler.WebUI.Forms.Widgets.CustomWidgets.WidgetValue.IsDefault() in Mendix.Modeler.WebUI\Forms\Widgets\CustomWidgets\WidgetValue.cs:line 1064 at Mendix.Modeler.WebUI.Forms.Widgets.CustomWidgets.CustomWidget.<>c.<HasInvalidPropertyValues>b__27_1(WidgetProperty p) in Mendix.Modeler.WebUI\Forms\Widgets\CustomWidgets\CustomWidget.cs:line 334 at System.Linq.Enumerable.Any[TSource](IEnumerable`1 source, Func`2 predicate) at Mendix.Modeler.WebUI.Forms.Widgets.CustomWidgets.CustomWidget.HasInvalidPropertyValues(Option`1 visibleProperties) in Mendix.Modeler.WebUI\Forms\Widgets\CustomWidgets\CustomWidget.cs:line 334 at Mendix.Modeler.WebUI.Forms.Widgets.CustomWidgets.CustomWidget.IsWidgetUpToDate(CustomWidgetType declaredWidgetType, Option`1 visibleProperties) in Mendix.Modeler.WebUI\Forms\Widgets\CustomWidgets\CustomWidget.cs:line 325 at Mendix.Modeler.WebUI.Forms.Widgets.CustomWidgets.CustomWidget.CheckWidgetType(IProblems problems, Option`1 visibleProperties) in Mendix.Modeler.WebUI\Forms\Widgets\CustomWidgets\CustomWidget.cs:line 217 at Mendix.Modeler.WebUI.Forms.Widgets.CustomWidgets.CustomWidget.CheckWidgetType(IProblems problems) in Mendix.Modeler.WebUI\Forms\Widgets\CustomWidgets\CustomWidget.cs:line 205 at Mendix.Modeler.WebUI.Forms.Documents.Bases.TemplateFormBase.Check(IProblems problems) in Mendix.Modeler.WebUI\Forms\Documents\Bases\TemplateFormBase.cs:line 52 at Mendix.Modeler.WebUI.Forms.Documents.BuildingBlocks.BuildingBlock.Check(IProblems problems) in Mendix.Modeler.WebUI\Forms\Documents\BuildingBlocks\BuildingBlock.cs:line 31 at Mendix.Modeler.Projects.Checks.DocumentCheck.<>c__DisplayClass5_0.<CheckDocument>b__2(ICheckable checkable) in Mendix.Modeler.Core\Projects\Checks\DocumentCheck.cs:line 39 at Mendix.Common.Util.EnumerableUtil.ForEach[T](IEnumerable`1 source, Action`1 action) in Mendix.Common\Util\EnumerableUtil.cs:line 51 at Mendix.Modeler.Projects.Checks.DocumentCheck.<>c__DisplayClass5_0.<CheckDocument>b__0() in Mendix.Modeler.Core\Projects\Checks\DocumentCheck.cs:line 39 at Mendix.Modeler.Common.ResolveCache.TrackResolves(Action code) in Mendix.Modeler.Core\Common\Problems\ResolveCache.cs:line 92 at Mendix.Modeler.Projects.Checks.DocumentCheck.CheckDocument(IDocument document, IProblems problems, CancellationToken cancellationToken) in Mendix.Modeler.Core\Projects\Checks\DocumentCheck.cs:line 38 at Mendix.Modeler.Projects.Checks.DocumentCheck.<>c__DisplayClass3_0.<Check>b__0(IDocument doc) in Mendix.Modeler.Core\Projects\Checks\DocumentCheck.cs:line 22 at Mendix.Modeler.Projects.Changes.ChangedDocumentsProcessor`1.<>c__DisplayClass6_0.<ProcessChangedDocuments>g__DoProcess|2(IDocument document) in Mendix.Modeler.Core\Projects\Changes\ChangedDocumentsProcessor.cs:line 76 at Mendix.Common.Util.EnumerableUtil.ForEach[T](IEnumerable`1 source, Action`1 action) in Mendix.Common\Util\EnumerableUtil.cs:line 51 at Mendix.Modeler.Projects.Changes.ChangedDocumentsProcessor`1.ProcessChangedDocuments(IProject project, ProjectChanges projectChanges, Func`2 processDocument) in Mendix.Modeler.Core\Projects\Changes\ChangedDocumentsProcessor.cs:line 70 at Mendix.Modeler.Projects.Checks.DocumentCheck.Check(IProject project, ProjectChanges changes, IProblems problems, CancellationToken cancellationToken) in Mendix.Modeler.Core\Projects\Checks\DocumentCheck.cs:line 21 at Mendix.Modeler.Projects.Checks.ProjectChecker.<>c__DisplayClass7_0.<RunProjectChecks>b__1(ProjectChanges changes) in Mendix.Modeler.Core\Projects\Checks\ProjectChecker.cs:line 76 at Mendix.Modeler.Projects.Changes.ChangedDocumentTracker.TryProcessChangesSync(Action`1 changeProcessor) in Mendix.Modeler.Core\Projects\Changes\ChangedDocumentTracker.cs:line 29 at Mendix.Modeler.Projects.Checks.ProjectChecker.<>c__DisplayClass7_0.<RunProjectChecks>b__0() in Mendix.Modeler.Core\Projects\Checks\ProjectChecker.cs:line 62 at Mendix.Modeler.Common.ResolveCache.<>c__DisplayClass10_0.<WithCache>b__0() in Mendix.Modeler.Core\Common\Problems\ResolveCache.cs:line 44 at Mendix.Modeler.Common.ResolveCache.WithCache[T](IProject project, Func`1 action) in Mendix.Modeler.Core\Common\Problems\ResolveCache.cs:line 62 at Mendix.Modeler.Common.ResolveCache.WithCache(IProject project, Action action) in Mendix.Modeler.Core\Common\Problems\ResolveCache.cs:line 40 at Mendix.Modeler.Projects.Checks.ProjectChecker.RunProjectChecks(IProject project, CancellationToken cancellationToken) in Mendix.Modeler.Core\Projects\Checks\ProjectChecker.cs:line 56 at Mendix.Modeler.Projects.Checks.ProjectChecker.<>c__DisplayClass5_0.<Check>b__0() in Mendix.Modeler.Core\Projects\Checks\ProjectChecker.cs:line 39 at Mendix.Modeler.ProtectedModules.ProtectedModulesUnlocker.ExecuteInContext[T](Boolean unlockImplementation, Func`1 code) in Mendix.Modeler.Core\ProtectedModules\ProtectedModulesUnlocker.cs:line 47 at Mendix.Modeler.ProtectedModules.ProtectedModulesUnlocker.Do[T](Boolean unlockImplementation, Func`1 action) in Mendix.Modeler.Core\ProtectedModules\ProtectedModulesUnlocker.cs:line 32 at Mendix.Modeler.Projects.Checks.ProjectChecker.Check(IProject project, CancellationToken cancellationToken) in Mendix.Modeler.Core\Projects\Checks\ProjectChecker.cs:line 39 at Mendix.Modeler.Core.View.Problems.BackgroundCheckRunner.Check(IProject project, CancellationToken cancellationToken) in Mendix.Modeler.Core.View\Problems\BackgroundCheckRunner.cs:line 44 at Mendix.Modeler.Core.View.Problems.BackgroundCheckRunner.Check(IProject project, CancellationToken cancellationToken) --- End of inner exception stack trace ---