diff --git a/Elwig/Windows/ChartWindow.xaml.cs b/Elwig/Windows/ChartWindow.xaml.cs
index c8521e3..cc1a86a 100644
--- a/Elwig/Windows/ChartWindow.xaml.cs
+++ b/Elwig/Windows/ChartWindow.xaml.cs
@@ -14,6 +14,8 @@ using ScottPlot.Plottables;
 using ScottPlot;
 using Xceed.Wpf.Toolkit.Primitives;
 using ScottPlot.Control;
+using System.Text.Json;
+using Microsoft.EntityFrameworkCore.Metadata.Internal;
 
 namespace Elwig.Windows {
     public partial class ChartWindow : ContextWindow {
@@ -101,12 +103,26 @@ namespace Elwig.Windows {
             PaymentVar = await Context.PaymentVariants.FindAsync(Year, AvNr) ?? throw new ArgumentException("PaymentVar not found");
             Season = await Context.Seasons.FindAsync(Year) ?? throw new ArgumentException("Season not found");
 
-            var data = EditBillingData.FromJson(PaymentVar.Data, Utils.GetVaributes(Context, Year));
-            var paymentEntries = data.GetPaymentGraphEntries(Context, Season);
-            GraphEntries = [
-                ..paymentEntries,
-                ..data.GetQualityGraphEntries(Context, Season, paymentEntries.Any() ? paymentEntries.Max(e => e.Id) : 0)
-            ];
+            try {
+                var data = EditBillingData.FromJson(PaymentVar.Data, Utils.GetVaributes(Context, Year));
+                var paymentEntries = data.GetPaymentGraphEntries(Context, Season);
+                GraphEntries = [
+                    ..paymentEntries,
+                    ..data.GetQualityGraphEntries(Context, Season, paymentEntries.Any() ? paymentEntries.Max(e => e.Id) : 0)
+                ];
+            } catch (KeyNotFoundException ex) {
+                var key = ex.Message.Split('\'')[1].Split('\'')[0];
+                MessageBox.Show($"Fehler beim Laden der Auszahlungsvariante:\n\n" +
+                    $"Mit unbekanntem Attribut '{key}' kann nicht umgegangen werden.", "Fehler",
+                    MessageBoxButton.OK, MessageBoxImage.Error);
+            } catch (ArgumentException) {
+                MessageBox.Show($"Fehler beim Laden der Auszahlungsvariante:\n\n" +
+                    $"Die Daten der Auszahlungsvariante entsprechen nicht dem benötigtem Format.", "Fehler",
+                    MessageBoxButton.OK, MessageBoxImage.Error);
+            } catch (Exception ex) {
+                MessageBox.Show("Fehler beim Laden der Auszahlungsvariante:\n\n" + ex.Message, "Fehler",
+                    MessageBoxButton.OK, MessageBoxImage.Error);
+            }
             Vaributes = Utils.GetVaributeList(Context, Year);
             GraphEntries.ForEach(e => {
                 e.Vaributes.ForEach(v => {