horizontal scroll not working in wpf usercontrol please help new to wpf

 <Grid Name="SP_ViewsMappingsDataGrid" Height="200" Width="600" VerticalAlignment="Top"  Margin="20,230,44,0"  HorizontalAlignment="Left" >
            <DataGrid AutoGenerateColumns="True" Margin="0,5,0,0" IsReadOnly="True" Height="Auto" Name="DGV_ViewMappings" Width="Auto" CanUserDeleteRows="False" CanUserAddRows="False" SelectionMode="Single" SelectionUnit="Cell" VerticalScrollBarVisibility="Visible" HorizontalScrollBarVisibility="Visible" Visibility="Hidden">
                <DataGrid.Columns>
                    <DataGridTemplateColumn Header="Action" >
                        <DataGridTemplateColumn.CellTemplate>
                            <DataTemplate>
                                <Button Click="Button_Click">Edit</Button>
                            </DataTemplate>
                        </DataGridTemplateColumn.CellTemplate>
                    </DataGridTemplateColumn>
                </DataGrid.Columns>
            </DataGrid>
        <!--</StackPanel>-->
        </Grid>