New Post: CheckComboBox and IDataErrorInfo and INotifyPropertyChanged

<xctk:CheckComboBox x:Name="checkResults"
                          ItemsSource="{Binding Path=AllowedValues}"
                          DisplayMemberPath="ResultText"
                          ValueMemberPath="ResultValue"
                          SelectedItemsOverride="{Binding Path=SelectedValues, Mode=TwoWay, UpdateSourceTrigger=LostFocus, ValidatesOnDataErrors=True, NotifyOnValidationError=True}"
                          ItemSelectionChanged="checkResults_ItemSelectionChanged"/>