I took your scenario and binded by creating the dependency property, for me everything works. Once the mouse is over the combo box and combobox has the focus , scrolling works fine with the mouse. you can only post a sample so that actual issue can be observed <ComboBox x:Name="cboDistrict" IsSynchronizedWithCurrentItem="True" Grid.Column="1" Grid.Row="0" Style="{DynamicResource BaseComboBox}" ItemsSource="{Binding Path=AllDistricts, Mode=Default}" SelectedItem="{Binding Path=BodyTextDistrict, Mode=TwoWay}"> <ComboBox.ItemTemplate> <DataTemplate> <TextBlock Text="{Binding }"/> </DataTemplate> </ComboBox.ItemTemplate> </ComboBox> Private Property AllDistricts() As ObservableCollection(Of String) Get Return DirectCast(GetValue(AllDistrictsProperty), ObservableCollection(Of String)) End Get Set(ByVal value As ObservableCollection(Of String)) SetValue(AllDistrictsProperty, value) End Set End Property Public Shared AllDistrictsProperty As DependencyProperty = _ DependencyProperty.Register("AllDistricts", GetType(ObservableCollection(Of String)), _ GetType(NameView), New UIPropertyMetadata(New ObservableCollection(Of String))) Public Property BodyTextDistrict() As String Get Return Convert.ToString(GetValue(BodyTextDistrictProperty)) End Get Set(ByVal value As String) SetValue(BodyTextDistrictProperty, value) End Set End Property Public Shared BodyTextDistrictProperty As DependencyProperty = _ DependencyProperty.Register("BodyTextDistrict", GetType(String), _ GetType(NameView), New UIPropertyMetadata(String.Empty))
