Opening a 4.8.10 version project using version 5.19.0 modeller locally (i.e. not logged in to Team Server) with a view to upgrading gives me this error: I am able to take other projects (4.1.1) to the 'do you want to convert' pop-up and this 4.8.10 project (upgraded from 4.1.1) also got that far in the past. Can anyone interpret this error message and let me know what I have to do to fix it? Many thanks, David Mendix.Modeler.Utility.Progress.ProgressException ---> System.InvalidOperationException: Opening the original project file failed. ---> System.NullReferenceException: Object reference not set to an instance of an object. at Mendix.Modeler.Integration.ConvertImportChoicePath.FindElementByRuntimePath(IElement element, IElementPath runtimePath) in c:\jenkins\workspace\AppStudio-Integration-Modeler\src\modeler\Mendix.Modeler.Integration\Conversions\ConvertImportChoicePath.cs:line 51 at Mendix.Modeler.Integration.ConvertImportChoicePath.UpdatePath(IMappingDocument importMapping, IMappingElement mappingElement) in c:\jenkins\workspace\AppStudio-Integration-Modeler\src\modeler\Mendix.Modeler.Integration\Conversions\ConvertImportChoicePath.cs:line 37 at Mendix.Modeler.Integration.ConvertImportChoicePath.ConvertPaths(ImportMapping importMapping) in c:\jenkins\workspace\AppStudio-Integration-Modeler\src\modeler\Mendix.Modeler.Integration\Conversions\ConvertImportChoicePath.cs:line 30 at Mendix.Modeler.Integration.ConvertImportChoicePath.Convert(IProject project) in c:\jenkins\workspace\AppStudio-Integration-Modeler\src\modeler\Mendix.Modeler.Integration\Conversions\ConvertImportChoicePath.cs:line 23 at Mendix.Modeler.Projects.Conversions.ProjectConversion.PerformOneTimeConversion(IOneTimeConversion oneTimeConversion) in c:\jenkins\workspace\AppStudio-Modeler\src\Mendix.Modeler.Core\Projects\Conversions\ProjectConversion.cs:line 57 at Mendix.Modeler.Projects.Conversions.ProjectConversion.DoOneTimeConversions() in c:\jenkins\workspace\AppStudio-Modeler\src\Mendix.Modeler.Core\Projects\Conversions\ProjectConversion.cs:line 41 at Mendix.Modeler.Projects.Project.<convert>b0() in c:\jenkins\workspace\AppStudio-Modeler\src\Mendix.Modeler.Core\Projects\Project.cs:line 320 at Mendix.Modeler.Projects.Project.HackProjectInstanceT in c:\jenkins\workspace\AppStudio-Modeler\src\Mendix.Modeler.Storage\Operations\TypeWalk.cs:line 87 at Mendix.Modeler.Storage.Operations.UnitLoader.IsConversionNeeded(IStorageUnit rootUnit) in c:\jenkins\workspace\AppStudio-Modeler\src\Mendix.Modeler.Storage\Operations\UnitLoader.cs:line 233 at Mendix.Modeler.Storage.Operations.UnitLoader.LoadT in c:\jenkins\workspace\AppStudio-Modeler\src\Mendix.Modeler.Utility\DbConnectors\DbConnector.cs:line 64 at Mendix.Modeler.Utility.DbConnectors.SQLiteConnector.DoTResult in c:\jenkins\workspace\AppStudio-Modeler\src\Mendix.Modeler.Storage\Database.cs:line 163 at Mendix.Modeler.Operations.Loader30.DoLoad(IProgressInfo info, String filePath) in c:\jenkins\workspace\AppStudio-Modeler\src\Mendix.Modeler.Core\Operations\Loader30.cs:line 17 --- End of inner exception stack trace --- at Mendix.Modeler.VersionControl.RevProjectBaseFileCache.ConvertBaseFileIfPossible(IProgressInfo info, Int64 desiredRevision) in c:\jenkins\workspace\AppStudio-Modeler\src\Mendix.Modeler.Core\VersionControl\RevProjectBaseFileCache.cs:line 81 at Mendix.Modeler.Main.ProjectFileOpener.<addconvertprojectbasefilestep>b1(IProgressInfo info) in c:\jenkins\workspace\AppStudio-Modeler\src\Mendix.Modeler.Core\Main\ProjectFileOpener.cs:line 105 at Mendix.Modeler.Utility.Progress.ProcessRunner.RunStep(Step step) in c:\jenkins\workspace\AppStudio-Modeler\src\Mendix.Modeler.UIFramework\Progress\ProcessRunner.cs:line 87 at Mendix.Modeler.Utility.Progress.ProcessRunner.worker_DoWork(Object sender, DoWorkEventArgs e) in c:\jenkins\workspace\AppStudio-Modeler\src\Mendix.Modeler.UIFramework\Progress\ProcessRunner.cs:line 67 at System.ComponentModel.BackgroundWorker.OnDoWork(DoWorkEventArgs e) at System.ComponentModel.BackgroundWorker.WorkerThreadStart(Object argument) --- End of inner exception stack trace --- at Mendix.Modeler.Utility.Progress.ProcessRunner.Run() in c:\jenkins\workspace\AppStudio-Modeler\src\Mendix.Modeler.UIFramework\Progress\ProcessRunner.cs:line 49 at Mendix.Modeler.Main.ProjectFileOpener.DoOpenProject() in c:\jenkins\workspace\AppStudio-Modeler\src\Mendix.Modeler.Core\Main\ProjectFileOpener.cs:line 89 at Mendix.Modeler.Main.ProjectFileOpener.OpenProject() in c:\jenkins\workspace\AppStudio-Modeler\src\Mendix.Modeler.Core\Main\ProjectFileOpener.cs:line 64 at Mendix.Modeler.Utility.FuncUtil.CallMeMaybe(Action action) in c:\jenkins\workspace\AppStudio-Modeler\src\Mendix.Modeler.Utility\FuncUtil.cs:line 26 at Mendix.Modeler.Utility.FuncUtil.CallMeMaybe(Action action) in c:\jenkins\workspace\AppStudio-Modeler\src\Mendix.Modeler.Utility\FuncUtil.cs:line 26 at System.Windows.EventRoute.InvokeHandlersImpl(Object source, RoutedEventArgs args, Boolean reRaised) at System.Windows.UIElement.RaiseEventImpl(DependencyObject sender, RoutedEventArgs args) at System.Windows.Controls.Primitives.ButtonBase.OnClick() at System.Windows.Controls.Button.OnClick() at System.Windows.Controls.Primitives.ButtonBase.OnMouseLeftButtonUp(MouseButtonEventArgs e) at System.Windows.RoutedEventArgs.InvokeHandler(Delegate handler, Object target) at System.Windows.RoutedEventHandlerInfo.InvokeHandler(Object target, RoutedEventArgs routedEventArgs) at System.Windows.EventRoute.InvokeHandlersImpl(Object source, RoutedEventArgs args, Boolean reRaised) at System.Windows.UIElement.ReRaiseEventAs(DependencyObject sender, RoutedEventArgs args, RoutedEvent newEvent) at System.Windows.UIElement.OnMouseUpThunk(Object sender, MouseButtonEventArgs e) at System.Windows.RoutedEventArgs.InvokeHandler(Delegate handler, Object target) at System.Windows.RoutedEventHandlerInfo.InvokeHandler(Object target, RoutedEventArgs routedEventArgs) at System.Windows.EventRoute.InvokeHandlersImpl(Object source, RoutedEventArgs args, Boolean reRaised) at System.Windows.UIElement.RaiseEventImpl(DependencyObject sender, RoutedEventArgs args) at System.Windows.UIElement.RaiseTrustedEvent(RoutedEventArgs args) at System.Windows.Input.InputManager.ProcessStagingArea() at System.Windows.Input.InputProviderSite.ReportInput(InputReport inputReport) at System.Windows.Interop.HwndMouseInputProvider.ReportInput(IntPtr hwnd, InputMode mode, Int32 timestamp, RawMouseActions actions, Int32 x, Int32 y, Int32 wheel) at System.Windows.Interop.HwndMouseInputProvider.FilterMessage(IntPtr hwnd, WindowMessage msg, IntPtr wParam, IntPtr lParam, Boolean& handled) at System.Windows.Interop.HwndSource.InputFilterMessage(IntPtr hwnd, Int32 msg, IntPtr wParam, IntPtr lParam, Boolean& handled) at MS.Win32.HwndWrapper.WndProc(IntPtr hwnd, Int32 msg, IntPtr wParam, IntPtr lParam, Boolean& handled) at MS.Win32.HwndSubclass.DispatcherCallbackOperation(Object o) at System.Windows.Threading.ExceptionWrapper.InternalRealCall(Delegate callback, Object args, Int32 numArgs) at System.Windows.Threading.ExceptionWrapper.TryCatchWhen(Object source, Delegate callback, Object args, Int32 numArgs, Delegate catchHandler)