I had a problem similar to this and I managed to solve it by following the steps provided in this question (https://community.mendix.com/link/space/studio-pro/questions/130824), but in some cases the following error occurs when I open a page in structure mode. System.ArgumentException: Font 'GLYPHICONS Halflings' does not support style 'Regular'. at System.Drawing.Font.CreateNativeFont() at System.Drawing.Font.Initialize(FontFamily family, Single emSize, FontStyle style, GraphicsUnit unit, Byte gdiCharSet, Boolean gdiVerticalFont) at System.Drawing.Font..ctor(FontFamily family, Single emSize, GraphicsUnit unit) at Mendix.Modeler.WebUI.View.Windows.StructureMode.Drawing.Iconss.LegacyGlyphFontManager.CacheFont(Int32 heightInPixels) in Mendix.Modeler.WebUI.View.Windows\StructureMode\Drawing\Iconss\GlyphFontManager.Legacy.cs:line 45 at System.Collections.Concurrent.ConcurrentDictionary`2.GetOrAdd(TKey key, Func`2 valueFactory) at Mendix.Modeler.WebUI.View.Windows.StructureMode.Drawing.ViewHelpers.ButtonConfig.WithIcon[T](T element, Func`1 getCaptionColor, ICustomIconCollectionFontCache customIconCollectionFontCache, ILegacyMxImageCache legacyMxImageCache, ILegacyImageConverter legacyImageConverter) in Mendix.Modeler.WebUI.View.Windows\StructureMode\Drawing\ViewHelpers\ButtonConfig.cs:line 56 at Mendix.Modeler.WebUI.View.Windows.StructureMode.Drawing.Views.Buttons.DrawableButtonView`1.GetButtonConfig(Boolean includeText) in Mendix.Modeler.WebUI.View.Windows\StructureMode\Drawing\Views\Buttons\DrawableButtonView.cs:line 63 at Mendix.Modeler.WebUI.View.Windows.StructureMode.Drawing.Views.Buttons.DrawableButtonView`1.CalculateContentSize(Graphics graphics, Int32 maxWidth) in Mendix.Modeler.WebUI.View.Windows\StructureMode\Drawing\Views\Buttons\DrawableButtonView.cs:line 40 at Mendix.Modeler.WebUI.View.Windows.StructureMode.Drawing.Views.OutlinedDrawableWidgetView`1.CalculateSizeInner(Graphics graphics, Int32 maxWidth) in Mendix.Modeler.WebUI.View.Windows\StructureMode\Drawing\Views\OutlinedDrawableWidgetView.cs:line 32 at Mendix.Modeler.WebUI.View.Windows.StructureMode.Drawing.ViewHelpers.DrawableWidgetContainerViewHelper.CalculateSize(Graphics graphics, Int32 maxWidth) in Mendix.Modeler.WebUI.View.Windows\StructureMode\Drawing\ViewHelpers\DrawableWidgetContainerViewHelper.cs:line 68 at Mendix.Modeler.WebUI.View.Windows.StructureMode.Drawing.Views.LayoutWidgets.DrawableDivContainerView.CalculateContentSize(Graphics graphics, Int32 maxWidth) in Mendix.Modeler.WebUI.View.Windows\StructureMode\Drawing\Views\LayoutWidgets\DrawableDivContainerView.cs:line 28 at Mendix.Modeler.WebUI.View.Windows.StructureMode.Drawing.Views.OutlinedDrawableWidgetView`1.CalculateSizeInner(Graphics graphics, Int32 maxWidth) in Mendix.Modeler.WebUI.View.Windows\StructureMode\Drawing\Views\OutlinedDrawableWidgetView.cs:line 32 at Mendix.Modeler.WebUI.View.Windows.StructureMode.Drawing.ViewHelpers.DrawableWidgetContainerViewHelper.CalculateSize(Graphics graphics, Int32 maxWidth) in Mendix.Modeler.WebUI.View.Windows\StructureMode\Drawing\ViewHelpers\DrawableWidgetContainerViewHelper.cs:line 68 at Mendix.Modeler.WebUI.View.Windows.StructureMode.Drawing.ViewHelpers.TopBottomViewHelper.CalculateSize(Graphics graphics, Int32 maxWidth) in Mendix.Modeler.WebUI.View.Windows\StructureMode\Drawing\ViewHelpers\TopBottomViewHelper.cs:line 22 at Mendix.Modeler.WebUI.View.Windows.StructureMode.Drawing.Views.EntityWidgets.DrawableEntityWidgetView`1.CalculateContentSize(Graphics graphics, Int32 maxWidth) in Mendix.Modeler.WebUI.View.Windows\StructureMode\Drawing\Views\EntityWidgets\DrawableEntityWidgetView.cs:line 58 at Mendix.Modeler.WebUI.View.Windows.StructureMode.Drawing.Views.OutlinedDrawableWidgetView`1.CalculateSizeInner(Graphics graphics, Int32 maxWidth) in Mendix.Modeler.WebUI.View.Windows\StructureMode\Drawing\Views\OutlinedDrawableWidgetView.cs:line 32 at Mendix.Modeler.WebUI.View.Windows.StructureMode.Drawing.ViewHelpers.DrawableWidgetContainerViewHelper.CalculateSize(Graphics graphics, Int32 maxWidth) in Mendix.Modeler.WebUI.View.Windows\StructureMode\Drawing\ViewHelpers\DrawableWidgetContainerViewHelper.cs:line 68 at Mendix.Modeler.WebUI.View.Windows.StructureMode.Drawing.Views.Documents.DrawableFormView.CalculateDimensions(Graphics graphics, Size canvasSize) in Mendix.Modeler.WebUI.View.Windows\StructureMode\Drawing\Views\Documents\DrawableFormView.cs:line 102 at Mendix.Modeler.WebUI.View.Windows.StructureMode.Drawing.Views.FormCalls.FormCallViewHelper.CalculateSize(Graphics graphics, Int32 maxWidth) in Mendix.Modeler.WebUI.View.Windows\StructureMode\Drawing\Views\FormCalls\FormCallViewHelper.cs:line 97 at Mendix.Modeler.WebUI.View.Windows.StructureMode.Drawing.Views.FormCalls.DrawableSnippetCallWidgetView.CalculateSizeInner(Graphics graphics, Int32 maxWidth) in Mendix.Modeler.WebUI.View.Windows\StructureMode\Drawing\Views\FormCalls\DrawableSnippetCallWidgetView.cs:line 28 at Mendix.Modeler.WebUI.View.Windows.StructureMode.Drawing.ViewHelpers.DrawableWidgetContainerViewHelper.CalculateSize(Graphics graphics, Int32 maxWidth) in Mendix.Modeler.WebUI.View.Windows\StructureMode\Drawing\ViewHelpers\DrawableWidgetContainerViewHelper.cs:line 68 at Mendix.Modeler.WebUI.View.Windows.StructureMode.Drawing.Views.LayoutWidgets.DrawableLayoutGridColumnView.CalculateSizeInner(Graphics graphics, Int32 maxWidth) in Mendix.Modeler.WebUI.View.Windows\StructureMode\Drawing\Views\LayoutWidgets\DrawableLayoutGridColumnView.cs:line 26 at Mendix.Modeler.WebUI.View.Windows.StructureMode.Drawing.Views.DrawableViewExtensions.CalculateSize(IDeterminesHeight view, Graphics graphics, Int32 maxWidth) in Mendix.Modeler.WebUI.View.Windows\StructureMode\Drawing\Views\DrawableViewExtensions.cs:line 30 at Mendix.Modeler.WebUI.View.Windows.StructureMode.Drawing.ViewHelpers.ViewHelperFromDeterminesHeight.CalculateSize(Graphics graphics, Int32 maxWidth) in Mendix.Modeler.WebUI.View.Windows\StructureMode\Drawing\ViewHelpers\ViewHelperFromDeterminesHeight.cs:line 16 at Mendix.Common.Util.EnumerableUtil.ForEach[T](IEnumerable`1 source, Action`1 action) in Mendix.Common\Util\EnumerableUtil.cs:line 51 at Mendix.Modeler.WebUI.View.Windows.StructureMode.Drawing.ViewHelpers.ColumnGroupViewHelper.SetColumnSizes(Graphics graphics, IList`1 flattenedWidths) in Mendix.Modeler.WebUI.View.Windows\StructureMode\Drawing\ViewHelpers\ColumnGroupViewHelper.cs:line 37 at Mendix.Modeler.WebUI.View.Windows.StructureMode.Drawing.ViewHelpers.ColumnGroupViewHelper.CalculateSize(Graphics graphics, Int32 maxWidth) in Mendix.Modeler.WebUI.View.Windows\StructureMode\Drawing\ViewHelpers\ColumnGroupViewHelper.cs:line 30 at Mendix.Modeler.WebUI.View.Windows.StructureMode.Drawing.Views.LayoutWidgets.DrawableLayoutGridRowView.CalculateSize(Graphics graphics, Int32 maxWidth) in Mendix.Modeler.WebUI.View.Windows\StructureMode\Drawing\Views\LayoutWidgets\DrawableLayoutGridRowView.cs:line 32 at Mendix.Modeler.WebUI.View.Windows.StructureMode.Drawing.Views.LayoutWidgets.DrawableLayoutGridView.CalculateContentSize(Graphics graphics, Int32 maxWidth) in Mendix.Modeler.WebUI.View.Windows\StructureMode\Drawing\Views\LayoutWidgets\DrawableLayoutGridView.cs:line 27 at Mendix.Modeler.WebUI.View.Windows.StructureMode.Drawing.Views.OutlinedDrawableWidgetView`1.CalculateSizeInner(Graphics graphics, Int32 maxWidth) in Mendix.Modeler.WebUI.View.Windows\StructureMode\Drawing\Views\OutlinedDrawableWidgetView.cs:line 32 at Mendix.Modeler.WebUI.View.Windows.StructureMode.Drawing.ViewHelpers.DrawableWidgetContainerViewHelper.CalculateSize(Graphics graphics, Int32 maxWidth) in Mendix.Modeler.WebUI.View.Windows\StructureMode\Drawing\ViewHelpers\DrawableWidgetContainerViewHelper.cs:line 68 at Mendix.Modeler.WebUI.View.Windows.StructureMode.Drawing.Views.LayoutWidgets.DrawableDivContainerView.CalculateContentSize(Graphics graphics, Int32 maxWidth) in Mendix.Modeler.WebUI.View.Windows\StructureMode\Drawing\Views\LayoutWidgets\DrawableDivContainerView.cs:line 28 at Mendix.Modeler.WebUI.View.Windows.StructureMode.Drawing.Views.OutlinedDrawableWidgetView`1.CalculateSizeInner(Graphics graphics, Int32 maxWidth) in Mendix.Modeler.WebUI.View.Windows\StructureMode\Drawing\Views\OutlinedDrawableWidgetView.cs:line 32 at Mendix.Modeler.WebUI.View.Windows.StructureMode.Drawing.ViewHelpers.DrawableWidgetContainerViewHelper.CalculateSize(Graphics graphics, Int32 maxWidth) in Mendix.Modeler.WebUI.View.Windows\StructureMode\Drawing\ViewHelpers\DrawableWidgetContainerViewHelper.cs:line 68 at Mendix.Modeler.WebUI.View.Windows.StructureMode.Drawing.ViewHelpers.DrawableWidgetContainerViewHelper.CalculateSizeAndReturnIt(Graphics graphics, Int32 maxWidth) in Mendix.Modeler.WebUI.View.Windows\StructureMode\Drawing\ViewHelpers\DrawableWidgetContainerViewHelper.cs:line 58 at Mendix.Modeler.WebUI.View.Windows.StructureMode.Drawing.Views.LayoutWidgets.DrawableScrollContainerRegionView.CalculateSizeInner(Graphics graphics, Int32 maxWidth) in Mendix.Modeler.WebUI.View.Windows\StructureMode\Drawing\Views\LayoutWidgets\DrawableScrollContainerRegionView.cs:line 64 at Mendix.Modeler.WebUI.View.Windows.StructureMode.Drawing.Views.DrawableViewExtensions.CalculateSize(IDeterminesHeight view, Graphics graphics, Int32 maxWidth) in Mendix.Modeler.WebUI.View.Windows\StructureMode\Drawing\Views\DrawableViewExtensions.cs:line 30 at Mendix.Modeler.WebUI.View.Windows.StructureMode.Drawing.ViewHelpers.ViewHelperFromDeterminesHeight.CalculateSize(Graphics graphics, Int32 maxWidth) in Mendix.Modeler.WebUI.View.Windows\StructureMode\Drawing\ViewHelpers\ViewHelperFromDeterminesHeight.cs:line 16 at Mendix.Modeler.WebUI.View.Windows.StructureMode.Drawing.ViewHelpers.RowViewHelper.CalculateSize(Graphics graphics, Int32 maxWidth) in Mendix.Modeler.WebUI.View.Windows\StructureMode\Drawing\ViewHelpers\RowViewHelper.cs:line 20 at Mendix.Modeler.WebUI.View.Windows.StructureMode.Drawing.ViewHelpers.DrawableColumnViewHelper.CalculateSize(Graphics graphics, Int32 maxWidth) in Mendix.Modeler.WebUI.View.Windows\StructureMode\Drawing\ViewHelpers\DrawableColumnViewHelper.cs:line 34 at Mendix.Modeler.WebUI.View.Windows.StructureMode.Drawing.Views.LayoutWidgets.DrawableScrollContainerView.CalculateSizeInner(Graphics graphics, Int32 maxWidth) in Mendix.Modeler.WebUI.View.Windows\StructureMode\Drawing\Views\LayoutWidgets\DrawableScrollContainerView.cs:line 101 at Mendix.Modeler.WebUI.View.Windows.StructureMode.Drawing.ViewHelpers.DrawableWidgetContainerViewHelper.CalculateSize(Graphics graphics, Int32 maxWidth) in Mendix.Modeler.WebUI.View.Windows\StructureMode\Drawing\ViewHelpers\DrawableWidgetContainerViewHelper.cs:line 68 at Mendix.Modeler.WebUI.View.Windows.StructureMode.Drawing.Views.Documents.DrawableFormView.CalculateDimensions(Graphics graphics, Size canvasSize) in Mendix.Modeler.WebUI.View.Windows\StructureMode\Drawing\Views\Documents\DrawableFormView.cs:line 102 at Mendix.Modeler.WebUI.View.Windows.StructureMode.Drawing.Views.FormCalls.FormCallViewHelper.CalculateSize(Graphics graphics, Int32 maxWidth) in Mendix.Modeler.WebUI.View.Windows\StructureMode\Drawing\Views\FormCalls\FormCallViewHelper.cs:line 97 at Mendix.Modeler.WebUI.View.Windows.StructureMode.Drawing.Views.Documents.DrawableFormView.CalculateDimensions(Graphics graphics, Size canvasSize) in Mendix.Modeler.WebUI.View.Windows\StructureMode\Drawing\Views\Documents\DrawableFormView.cs:line 102 at Mendix.Modeler.WebUI.View.Windows.StructureMode.Drawing.Views.Documents.DrawableFormView.CalculateDimensions(Graphics graphics) in Mendix.Modeler.WebUI.View.Windows\StructureMode\Drawing\Views\Documents\DrawableFormView.cs:line 95 at Mendix.Modeler.WebUI.View.Windows.FormEditorControls.FormEditorControl.RefreshContents() in Mendix.Modeler.WebUI.View.Windows\FormEditorControls\FormEditorControl.cs:line 183 at Mendix.Modeler.WebUI.View.Windows.StructureMode.StructureModeEditor.RefreshContents() in Mendix.Modeler.WebUI.View.Windows\StructureMode\StructureModeEditor.cs:line 234 at Mendix.Modeler.WebUI.View.Windows.StructureMode.StructureModeEditor.ShowControl() in Mendix.Modeler.WebUI.View.Windows\StructureMode\StructureModeEditor.cs:line 124 at Mendix.Modeler.WebUI.View.Editors.FormEditor.SetActiveEditor(IPageEditor value, Boolean isInitialLoad) in Mendix.Modeler.WebUI.View\Editors\FormEditor.cs:line 317 at Mendix.Modeler.WebUI.View.Editors.FormEditor.OpenStructureMode(Boolean isInitialLoad) in Mendix.Modeler.WebUI.View\Editors\FormEditor.cs:line 268 at Mendix.Modeler.WebUI.View.Editors.FormEditor.SetInitialEditor() in Mendix.Modeler.WebUI.View\Editors\FormEditor.cs:line 248 at Mendix.Modeler.WebUI.View.Editors.FormEditor.Initialize(IFormBase form, IList`1 notificationBarFactories) in Mendix.Modeler.WebUI.View\Editors\FormEditor.cs:line 226 at Mendix.Modeler.WebUI.View.Editors.FormEditor..ctor(IFormBase form, IProjectManager projectManager, IStorageUI storageUI, IToolWindowManager toolWindowManager, IClipboard clipboard, IDialogs dialogs, IModelerSettingsManager modelerSettingsManager, IPageEditorProvider pageEditorProvider, IGuiThreadExecutor guiThreadExecutor, IActiveProblemsManager activeProblemsManager, IBestPracticeBotController bestPracticeBotController, IAnalyticsEventManager analyticsEventManager, IBuildingBlockProvider buildingBlockProvider, IWidgetPackageManager widgetPackageManager, IEnumerable`1 notificationBarFactories, ITabbedEditorManager tabbedEditorManager, IDocumentViewManager documentViewManager, IWidgetToolRegistry widgetToolRegistry, IDialogManager dialogManager, IFormEditorSelectionHelper selectionHelper) in Mendix.Modeler.WebUI.View\Editors\FormEditor.cs:line 160 at Mendix.Modeler.WebUI.View.Editors.FormEditorFactory.Create(FormBase form) in Mendix.Modeler.WebUI.View\Editors\FormEditorFactory.cs:line 89 at Mendix.Modeler.WebUI.View.Documents.FormBaseViewProvider`1.CreateTabbedEditor(TDocument document) in Mendix.Modeler.WebUI.View\Documents\FormBaseViewProvider.cs:line 19 at Mendix.Modeler.Core.View.Editors.TabbedDocumentViewProviderBase`1.Mendix.Modeler.Core.View.Editors.IDocumentViewProvider.CreateTabbedEditor(IDocumentBase document) in Mendix.Modeler.Core.View\Editors\TabbedEditors\TabbedDocumentViewProviderBase.cs:line 13 at Mendix.Modeler.Core.View.MainWindow.DockControlViewModel.<>c__DisplayClass65_0.<AddTabbedEditor>b__1() in Mendix.Modeler.Core.View\MainWindow\DockControlViewModel.cs:line 234 at Mendix.Modeler.Controls.GuiThreadExecutor.<>c__DisplayClass5_0`1.<WrapActionWithRethrowHack>b__0() in Mendix.Modeler.Controls\GuiThreadExecutor.cs:line 64--- End of stack trace from previous location --- at Mendix.Modeler.Controls.GuiThreadExecutor.Rethrow(Exception ex) in Mendix.Modeler.Controls\GuiThreadExecutor.cs:line 69 at Mendix.Modeler.Controls.GuiThreadExecutor.<>c__DisplayClass5_0`1.<WrapActionWithRethrowHack>b__0() in Mendix.Modeler.Controls\GuiThreadExecutor.cs:line 64 at Eto.Forms.Application.<>c__DisplayClass67_0`1.<Invoke>b__0() at Eto.Forms.Application.Invoke[T](Func`1 func) at Mendix.Modeler.Core.View.MainWindow.DockControlViewModel.AddTabbedEditor(IDocumentBase document) in Mendix.Modeler.Core.View\MainWindow\DockControlViewModel.cs:line 233 at Mendix.Modeler.MainWindow.Managers.TabbedEditorManager.EditDocument(IDocumentBase document) in Mendix.Modeler.MainWindow\Managers\TabbedEditorManager.cs:line 69 at Mendix.Modeler.Core.View.Editors.DocumentViewManager.EditInTabbedEditor(IDocument document, FocusInfo focusInfo) in Mendix.Modeler.Core.View\Editors\DocumentViewManager.cs:line 89 at Mendix.Modeler.Core.View.Editors.DocumentViewManager.EditDocument(IDocument document, FocusInfo focusInfo) in Mendix.Modeler.Core.View\Editors\DocumentViewManager.cs:line 69 at Mendix.Modeler.Common.DocumentUtil.ObsoleteEdit(IDocument document, FocusInfo focusInfo) in Mendix.Modeler.Core\Common\Model\DocumentUtil.cs:line 15 at Mendix.Modeler.Projects.ProjectExplorers.DocumentNode.ActivateNode() in Mendix.Modeler.Core\Projects\ProjectExplorers\DocumentNode.cs:line 35 at Mendix.Modeler.Core.View.ToolWindows.ProjectExplorer.<>c.<OnActivated>b__33_0(IProjectExplorerNode node) in Mendix.Modeler.Core.View\ToolWindows\ProjectExplorer\ProjectExplorer.cs:line 154 at System.Collections.Generic.List`1.ForEach(Action`1 action) at Mendix.Modeler.Core.View.ToolWindows.ProjectExplorer.OnActivated(IEnumerable`1 nodes) in Mendix.Modeler.Core.View\ToolWindows\ProjectExplorer\ProjectExplorer.cs:line 154 at Mendix.Modeler.Controls.Tree.TreeViewModel`2.RaiseActivated() in Mendix.Modeler.Controls\Tree\ViewModels\TreeViewModel.cs:line 302 at Mendix.Modeler.Controls.Tree.TreeControl`2.OnActivated(Object sender, TreeGridViewItemEventArgs e) in Mendix.Modeler.Controls\Tree\Views\TreeControl.cs:line 194 at Eto.PropertyStore.TriggerEvent[T](Object key, Object sender, T args) at Eto.Forms.TreeGridView.OnActivated(TreeGridViewItemEventArgs e) at Mendix.Modeler.Controls.Tree.TreeControl`2.RaiseActivated() in Mendix.Modeler.Controls\Tree\Views\TreeControl.cs:line 140 at Mendix.Modeler.Controls.Tree.TreeControlMouseHandler`2.OnTreeItemMouseDoubleClick(MouseEventArgs e) in Mendix.Modeler.Controls\Tree\Views\TreeControlMouseHandler.cs:line 31 at Mendix.Modeler.Controls.Tree.IconsAndLabelTreeColumn.InvokeMouseAction(Object s, MouseEventArgs e, Action`1 action) in Mendix.Modeler.Controls\Tree\Views\Columns\IconsAndLabelTreeColumn.cs:line 52 at Mendix.Modeler.Controls.Tree.IconsAndLabelTreeColumn.<Init>b__20_4(Object s, MouseEventArgs e) in Mendix.Modeler.Controls\Tree\Views\Columns\IconsAndLabelTreeColumn.cs:line 39 at Mendix.Modeler.Controls.Windows.Tree.IconsAndLabelTreeColumnHandler.Column.<>c__DisplayClass11_0.<BindEventHandlers>b__2(Object s, MouseButtonEventArgs e) in Mendix.Modeler.Controls.Windows\Tree\IconsAndLabelTreeColumnHandler.cs:line 199 at System.Windows.RoutedEventArgs.InvokeHandler(Delegate handler, Object target) at System.Windows.EventRoute.InvokeHandlersImpl(Object source, RoutedEventArgs args, Boolean reRaised) at System.Windows.UIElement.RaiseEventImpl(DependencyObject sender, RoutedEventArgs args) at System.Windows.ContentElement.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)