diff --git a/Elwig/Dialogs/UpdateDialog.xaml b/Elwig/Dialogs/UpdateDialog.xaml
index 570c656..58ea9f7 100644
--- a/Elwig/Dialogs/UpdateDialog.xaml
+++ b/Elwig/Dialogs/UpdateDialog.xaml
@@ -5,9 +5,10 @@
         xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
         ResizeMode="NoResize" ShowInTaskbar="False" Topmost="True"
         WindowStartupLocation="CenterOwner"
-        Title="Neues Update verfügbar - Elwig" Height="180" Width="400">
+        Title="Neues Update verfügbar - Elwig" Height="190" Width="400"
+        Closed="OnClosed">
     <Grid>
-        <TextBlock x:Name="Description" FontSize="14" Margin="0,0,0,30"
+        <TextBlock x:Name="Description" FontSize="14" Margin="0,0,0,40"
                    HorizontalAlignment="Center" VerticalAlignment="Center" TextAlignment="Center">
             Version <Run x:Name="VersionText" FontWeight="Bold">0.0.0</Run> von Elwig ist verfügbar!
             (<Hyperlink NavigateUri="https://elwig.at/changelog" RequestNavigate="Hyperlink_RequestNavigate">Änderungen</Hyperlink>)<LineBreak/>
@@ -20,12 +21,12 @@
                      HorizontalAlignment="Center" VerticalAlignment="Center"
                      Height="27" Width="300" SnapsToDevicePixels="True"/>
 
-        <Button x:Name="InstallButton" Content="Installieren" Margin="10,10,115,10"
-                FontSize="14" HorizontalAlignment="Right" VerticalAlignment="Bottom"
+        <Button x:Name="InstallButton" Content="Installieren" Margin="10,10,115,20"
+                FontSize="14" HorizontalAlignment="Center" VerticalAlignment="Bottom"
                 Width="100" Height="27"
                 Click="InstallButton_Click"/>
-        <Button x:Name="CancelButton" Content="Abbrechen" Margin="10,10,10,10" IsCancel="True" IsDefault="True"
-                FontSize="14" HorizontalAlignment="Right" VerticalAlignment="Bottom"
+        <Button x:Name="CancelButton" Content="Abbrechen" Margin="115,10,10,20" IsCancel="True"
+                FontSize="14" HorizontalAlignment="Center" VerticalAlignment="Bottom"
                 Width="100" Height="27"/>
     </Grid>
 </Window>
diff --git a/Elwig/Dialogs/UpdateDialog.xaml.cs b/Elwig/Dialogs/UpdateDialog.xaml.cs
index 84d22c9..e8f498a 100644
--- a/Elwig/Dialogs/UpdateDialog.xaml.cs
+++ b/Elwig/Dialogs/UpdateDialog.xaml.cs
@@ -3,6 +3,7 @@ using System;
 using System.Diagnostics;
 using System.IO;
 using System.Net.Http;
+using System.Threading;
 using System.Threading.Tasks;
 using System.Windows;
 using System.Windows.Navigation;
@@ -13,36 +14,47 @@ namespace Elwig.Dialogs {
         public string Version { get; private set; }
         public string Url { get; private set; }
 
+        private readonly CancellationTokenSource Cancellation;
+
         public UpdateDialog(string version, string url, long size) {
             Version = version;
             Url = url;
+            Cancellation = new();
             InitializeComponent();
             VersionText.Text = version;
             SizeText.Text = $"{size / 1024 / 1024}";
         }
 
+        private void OnClosed(object sender, EventArgs evt) {
+            Cancellation.Cancel();
+        }
+
         private async void InstallButton_Click(object sender, RoutedEventArgs evt) {
             Description.Visibility = Visibility.Hidden;
             ProgressBar.Visibility = Visibility.Visible;
             InstallButton.IsEnabled = false;
             await Install();
-            DialogResult = true;
             Close();
         }
 
         public async Task Install() {
             var fileName = Path.Combine(App.TempPath, $"Elwig-{Version}.exe");
-            {
+            try {
                 using var stream = new FileStream(fileName, FileMode.Create);
                 using var client = new HttpClient() {
                     Timeout = TimeSpan.FromSeconds(5),
                 };
                 await client.DownloadAsync(Url, stream, new Progress<double>(p => {
                     ProgressBar.Value = p * 100.0;
-                }));
+                }), Cancellation.Token);
+            } catch (OperationCanceledException) {
+                File.Delete(fileName);
+                return;
+            } catch (Exception exc) {
+                MessageBox.Show(exc.Message, "Fehler", MessageBoxButton.OK, MessageBoxImage.Error);
             }
-
             Process.Start(fileName);
+            DialogResult = true;
         }
 
         private void Hyperlink_RequestNavigate(object sender, RequestNavigateEventArgs e) {