1 files changed, 6 insertions, 4 deletions
diff --git a/win/CS/HandBrakeWPF/Converters/InverseBooleanConverter.cs b/win/CS/HandBrakeWPF/Converters/InverseBooleanConverter.cs
index 8cd29431f..b935953eb 100644
--- a/win/CS/HandBrakeWPF/Converters/InverseBooleanConverter.cs
+++ b/win/CS/HandBrakeWPF/Converters/InverseBooleanConverter.cs
@@ -16,7 +16,7 @@ namespace HandBrakeWPF.Converters
     /// <summary>
     /// The inverse boolean converter.
     /// </summary>
-    [ValueConversion(typeof(bool), typeof(bool))]
+    [ValueConversion(typeof(bool?), typeof(bool))]
     public class InverseBooleanConverter : IValueConverter
     {
         /// <summary>
@@ -39,12 +39,14 @@ namespace HandBrakeWPF.Converters
         /// </returns>
         public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
         {
-            if (targetType != typeof(bool))
+            if (targetType != typeof(bool?) && targetType != typeof(bool))
             {
                 throw new InvalidOperationException("The target must be a boolean");
             }
 
-            return !(bool)value;
+            bool result;
+            bool.TryParse(value.ToString(), out result);
+            return !result;
         }
 
         /// <summary>
@@ -67,7 +69,7 @@ namespace HandBrakeWPF.Converters
         /// </returns>
         public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture)
         {
-            throw new NotSupportedException();
+            return null;
         }
     }
 }
 \ No newline at end of file