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.CustomWidget.WriteWidget(IFormWriter formWriter, IWebExportContext context) in Mendix.Modeler.WebUI\Forms\Widgets\CustomWidgets\CustomWidget.cs:line 345 at Mendix.Modeler.WebUI.Forms.Exporter.FormWriter.WriteWidget(IWriteWidget widget, IWebExportContext context) in Mendix.Modeler.WebUI\Forms\Exporter\FormWriter.cs:line 100 at Mendix.Modeler.WebUI.Forms.Widgets.EntityWidgets.DataViews.DataView.<>c__DisplayClass29_0.<WriteTemplates>b__0() in Mendix.Modeler.WebUI\Forms\Widgets\EntityWidgets\DataViews\DataView.cs:line 239 at Mendix.Modeler.WebUI.Forms.Exporter.FormWriter.WriteTemplate(IExportContext context, IDocumentObject documentObject, String templateName, Action writeTemplate) in Mendix.Modeler.WebUI\Forms\Exporter\FormWriter.cs:line 142 at Mendix.Modeler.WebUI.Forms.Widgets.EntityWidgets.DataViews.DataView.WriteTemplates(FormWriter formWriter, IWebExportContext context) in Mendix.Modeler.WebUI\Forms\Widgets\EntityWidgets\DataViews\DataView.cs:line 251 at Mendix.Modeler.WebUI.Forms.Exporter.FormWriter.WriteTemplates() in Mendix.Modeler.WebUI\Forms\Exporter\FormWriter.cs:line 92 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 193 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 92 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 82 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 63 at Mendix.Modeler.WebUI.Deployment.WebUIDeploymentWorker.ExportPages(IProject project, IProgressInfo info, Boolean updateRunningProject) in Mendix.Modeler.WebUI\Deployment\WebUIDeploymentWorker.cs:line 207 at Mendix.Modeler.WebUI.Deployment.WebUIDeploymentWorker.DoWork(DeploymentPhase phase, IProject project, DeploymentSettings settings, IProgressInfo info) in Mendix.Modeler.WebUI\Deployment\WebUIDeploymentWorker.cs:line 110 at Mendix.Modeler.Deployment.DeploymentProcessBuilder.ExecuteDeploymentWorkForPhase(DeploymentPhase phase, IProject project, DeploymentSettings settings, IProgressInfo info) in Mendix.Modeler.Deployment\DeploymentProcessBuilder.cs:line 187 at Mendix.Modeler.Deployment.DeploymentProcessBuilder.<>c__DisplayClass13_1.<AddBuildStepWithOverride>b__2() in Mendix.Modeler.Deployment\DeploymentProcessBuilder.cs:line 157 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 156 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 155 at Mendix.Modeler.Deployment.FileIOExceptionHandlingProcess.<>c__DisplayClass2_1.<AddStep>b__1() in Mendix.Modeler.Core\Deployment\FileIOExceptionHandlingProcess.cs:line 22 at Mendix.Modeler.Deployment.FileIOExceptionHandlingProcess.CatchDiskException(Action action) in Mendix.Modeler.Core\Deployment\FileIOExceptionHandlingProcess.cs:line 31 at Mendix.Modeler.Deployment.FileIOExceptionHandlingProcess.<>c__DisplayClass2_0.<AddStep>b__0(IProgressInfo info) in Mendix.Modeler.Core\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 167 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 85