diff --git a/CHANGELOG.md b/CHANGELOG.md
index b6c5981d..eee198d6 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -8,6 +8,8 @@
 
 - Initial GA Actions Support
 - Added New Target .NET 7.0
+- Fix TaskDialog.DefaultButton property is ignored
+- remove first dot in extension
 
 ### 2022-11-04
 
diff --git a/source/WindowsAPICodePack/Core/Dialogs/TaskDialogs/TaskDialog.cs b/source/WindowsAPICodePack/Core/Dialogs/TaskDialogs/TaskDialog.cs
index 9765b364..1ee9aab5 100644
--- a/source/WindowsAPICodePack/Core/Dialogs/TaskDialogs/TaskDialog.cs
+++ b/source/WindowsAPICodePack/Core/Dialogs/TaskDialogs/TaskDialog.cs
@@ -815,7 +815,11 @@ private void ApplyControlConfiguration(NativeTaskDialogSettings settings)
                 }
 
                 // Set default button and add elevation icons to appropriate buttons.
-                settings.NativeConfiguration.defaultButtonIndex = FindDefaultButtonId(sourceList);
+                var defaultBtn = FindDefaultButtonId(sourceList);
+                if (defaultBtn != TaskDialogNativeMethods.NoDefaultButtonSpecified)
+                {
+                    settings.NativeConfiguration.defaultButtonIndex = defaultBtn;
+                }
 
                 ApplyElevatedIcons(settings, sourceList);
             }
diff --git a/source/WindowsAPICodePack/Shell/CommonFileDialogs/CommonFileDialogFilter.cs b/source/WindowsAPICodePack/Shell/CommonFileDialogs/CommonFileDialogFilter.cs
index 2f3dbfb4..30b0b147 100644
--- a/source/WindowsAPICodePack/Shell/CommonFileDialogs/CommonFileDialogFilter.cs
+++ b/source/WindowsAPICodePack/Shell/CommonFileDialogs/CommonFileDialogFilter.cs
@@ -128,7 +128,7 @@ private static string NormalizeExtension(string rawExtension)
             int indexOfDot = rawExtension.IndexOf('.');
             if (indexOfDot != -1)
             {
-                rawExtension.Remove(indexOfDot);
+                rawExtension = rawExtension.Substring(indexOfDot + 1);
             }
 
             return rawExtension;