diff --git a/ILSpy/App.axaml.cs b/ILSpy/App.axaml.cs
index f2b3d5c70..64edee8e9 100644
--- a/ILSpy/App.axaml.cs
+++ b/ILSpy/App.axaml.cs
@@ -78,17 +78,40 @@ namespace ILSpy
 				StartupExceptions.Items.Add(new ExceptionData(ex));
 			}
 
-			if (Composition?.GetExport<SettingsService>() is { } settingsService)
+			try
+			{
+				if (Composition?.GetExport<SettingsService>() is { } settingsService)
+				{
+					ThemeManager.Current.Attach(settingsService.SessionSettings);
+					ApplyCulture(settingsService.SessionSettings.CurrentCulture);
+				}
+			}
+			catch (Exception ex)
 			{
-				ThemeManager.Current.Attach(settingsService.SessionSettings);
-				ApplyCulture(settingsService.SessionSettings.CurrentCulture);
+				StartupExceptions.Items.Add(new ExceptionData(ex));
 			}
 
 			if (ApplicationLifetime is IClassicDesktopStyleApplicationLifetime desktop)
 			{
-				AppLog.Mark("MainWindow about to be resolved from MEF");
-				desktop.MainWindow = Composition?.GetExport<MainWindow>()
-					?? new MainWindow();
+				MainWindow? mainWindow = null;
+				try
+				{
+					AppLog.Mark("MainWindow about to be resolved from MEF");
+					mainWindow = Composition?.GetExport<MainWindow>();
+				}
+				catch (Exception ex)
+				{
+					StartupExceptions.Items.Add(new ExceptionData(ex));
+				}
+
+				// Without this fallback, anything thrown by MEF resolution above propagates out of
+				// OnFrameworkInitializationCompleted before the dispatcher pump starts -- so the
+				// AppDomain.UnhandledException dialog posted by GlobalExceptionHandler never gets
+				// a chance to run, and the user sees a silent exit. Hand the user a window that
+				// shows the captured exceptions instead.
+				desktop.MainWindow = StartupExceptions.Items.Count > 0
+					? new StartupErrorWindow(StartupExceptions.Items)
+					: mainWindow ?? new MainWindow();
 				AppLog.Mark("MainWindow assigned to desktop.MainWindow");
 				desktop.Exit += (_, _) => {
 					try
diff --git a/ILSpy/AppEnv/StartupErrorWindow.cs b/ILSpy/AppEnv/StartupErrorWindow.cs
new file mode 100644
index 000000000..07ff581a4
--- /dev/null
+++ b/ILSpy/AppEnv/StartupErrorWindow.cs
@@ -0,0 +1,112 @@
+// Copyright (c) 2026 AlphaSierraPapa for the SharpDevelop Team
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy of this
+// software and associated documentation files (the "Software"), to deal in the Software
+// without restriction, including without limitation the rights to use, copy, modify, merge,
+// publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons
+// to whom the Software is furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in all copies or
+// substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
+// INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR
+// PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE
+// FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
+// OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+// DEALINGS IN THE SOFTWARE.
+
+using System.Collections.Generic;
+
+using global::Avalonia;
+using global::Avalonia.Controls;
+using global::Avalonia.Input;
+using global::Avalonia.Input.Platform;
+using global::Avalonia.Layout;
+using global::Avalonia.Media;
+
+using CommunityToolkit.Mvvm.Input;
+
+namespace ILSpy.AppEnv
+{
+	/// <summary>
+	/// Shown in place of the main window when startup fails before the dispatcher pump begins.
+	/// Without this, a CompositionFailedException (e.g. an unresolvable plugin dependency)
+	/// would propagate out of App.OnFrameworkInitializationCompleted and the process would
+	/// die before <see cref="GlobalExceptionHandler"/> could surface a dialog.
+	/// </summary>
+	internal sealed class StartupErrorWindow : Window
+	{
+		public StartupErrorWindow(IList<ExceptionData> exceptions)
+		{
+			Title = "ILSpy -- startup failed";
+			Width = 720;
+			Height = 480;
+			WindowStartupLocation = WindowStartupLocation.CenterScreen;
+
+			var clipboardText = StartupExceptions.Format();
+			var details = new TextBox {
+				IsReadOnly = true,
+				AcceptsReturn = true,
+				TextWrapping = TextWrapping.NoWrap,
+				FontFamily = new FontFamily("Consolas, Menlo, Monospace"),
+				FontSize = 12,
+				Text = clipboardText,
+			};
+
+			var summary = new TextBlock {
+				Margin = new Thickness(0, 0, 0, 8),
+				FontWeight = FontWeight.Bold,
+				TextWrapping = TextWrapping.Wrap,
+				Text = exceptions.Count == 1
+					? "ILSpy could not start because of a startup error."
+					: $"ILSpy could not start: {exceptions.Count} startup errors occurred.",
+			};
+
+			var copy = new Button { Content = "Copy" };
+			copy.Click += (_, _) => CopyToClipboard(clipboardText);
+
+			var exit = new Button { Content = "Exit", IsDefault = true };
+			exit.Click += (_, _) => Close();
+
+			var buttons = new StackPanel {
+				Orientation = Orientation.Horizontal,
+				HorizontalAlignment = HorizontalAlignment.Right,
+				Margin = new Thickness(0, 8, 0, 0),
+				Spacing = 8,
+				Children = { copy, exit },
+			};
+
+			var grid = new Grid {
+				Margin = new Thickness(12),
+				RowDefinitions = new RowDefinitions("Auto,*,Auto"),
+			};
+			Grid.SetRow(summary, 0);
+			Grid.SetRow(details, 1);
+			Grid.SetRow(buttons, 2);
+			grid.Children.Add(summary);
+			grid.Children.Add(details);
+			grid.Children.Add(buttons);
+
+			Content = grid;
+
+			KeyBindings.Add(new KeyBinding {
+				Gesture = new KeyGesture(Key.C, KeyModifiers.Control),
+				Command = new RelayCommand(
+					() => CopyToClipboard(clipboardText),
+					() => string.IsNullOrEmpty(details.SelectedText)),
+			});
+			KeyBindings.Add(new KeyBinding {
+				Gesture = new KeyGesture(Key.Escape),
+				Command = new RelayCommand(Close),
+			});
+		}
+
+		void CopyToClipboard(string text)
+		{
+			var clipboard = TopLevel.GetTopLevel(this)?.Clipboard;
+			if (clipboard != null)
+				_ = clipboard.SetTextAsync(text);
+		}
+	}
+}