Scroll Viewer not visible in wpf DataGrid

I have a datagrid in a grid but the scrollviewer is not visibile even though I made it auto. Below in my code. I can't figure out where's the problem.

    <Grid Grid.Row="0" Grid.Column="0">
        <Grid.RowDefinitions>
            <RowDefinition Height="Auto" ></RowDefinition>
            <RowDefinition Height="Auto" ></RowDefinition>
            <RowDefinition Height="Auto" ></RowDefinition>
            <RowDefinition Height="Auto" ></RowDefinition>
            <RowDefinition Height="Auto" ></RowDefinition>
            <RowDefinition Height="Auto" ></RowDefinition>
            <RowDefinition Height="Auto" ></RowDefinition>
            <RowDefinition Height="Auto" ></RowDefinition>
            <RowDefinition Height="Auto"></RowDefinition>
            <RowDefinition Height="Auto"></RowDefinition>
        </Grid.RowDefinitions>
        <Grid.ColumnDefinitions>
            <ColumnDefinition Width="Auto"></ColumnDefinition>
            <ColumnDefinition Width="Auto"></ColumnDefinition>
        </Grid.ColumnDefinitions>

        <TextBlock Text="Doctor Name" Grid.Row="0" Grid.Column="0" Margin="5,5,0,0"/>
        <TextBlock Text="Doctor Address" Grid.Row="1" Grid.Column="0" Margin="5,5,0,0"/>
        <TextBlock Text="Entry Note" Grid.Row="2" Grid.Column="0" Margin="5,5,0,0"/>
        <TextBlock Text="Join Date" Grid.Row="3" Grid.Column="0" Margin="5,5,0,0"/>
        <TextBlock Text="Default Discount" Grid.Row="4" Grid.Column="0" Margin="5,5,0,0"/>
        <TextBlock Text="Discount Valid Till" Grid.Row="5" Grid.Column="0" Margin="5,5,0,0"/>
        <TextBlock Text="Employee Name" Grid.Row="6" Grid.Column="0" Margin="5,5,0,0"/>

        <Grid Grid.Row="7" Grid.Column="0" Grid.ColumnSpan="2">
            <Grid.ColumnDefinitions>
                <ColumnDefinition></ColumnDefinition>
                <ColumnDefinition></ColumnDefinition>
                <ColumnDefinition></ColumnDefinition>
            </Grid.ColumnDefinitions>

            <TextBlock Text="Report Type" Grid.Row="0" Grid.Column="0" Margin="5,5,0,0"/>
            <ComboBox Grid.Row="0" Grid.Column="1" Name="cmbReportType" Text="{Binding CurrentEntity.ReportType}"/>
            <Button Grid.Row="0" Grid.Column="2" Name="btnAddDetail" Content="Add Details" Command="{Binding AddDetailsCommand}"/>
        </Grid>           

        <TextBox Grid.Row="0" Grid.Column="1" Margin="5,5,0,0" Width="190" Name="txtDocName" Text="{Binding CurrentEntity.RefName}"/>
        <TextBox Grid.Row="1" Grid.Column="1" Margin="5,5,0,0" Width="190" Height="75" Name="txtDocAddress" Text="{Binding CurrentEntity.RefAddress}"/>
        <TextBox Grid.Row="2" Grid.Column="1" Margin="5,5,0,0" Width="190" Height="100" Name="txtEntryNote" Text="{Binding CurrentEntity.EntryNotes}"/>

        <Custom:DatePicker Grid.Row="3" Grid.Column="1" Margin="5,3,0,0" Width="125" Name="dtpJoinDate" Height="24" HorizontalAlignment="Left" VerticalAlignment="Top" SelectedDate="{Binding CurrentEntity.DateStarted}" SelectedDateFormat="Short"/>

        <TextBox Grid.Row="4" Grid开发者_如何学Python.Column="1" Height="25" Width="75" Name="txtDefaultDiscount" HorizontalAlignment="Left" Margin="5,0,0,0" VerticalAlignment="Top" Text="{Binding CurrentEntity.DefaultDiscount}"/>

        <Custom:DatePicker Grid.Row="5" Grid.Column="1" Margin="5,3,0,0" Width="125" Name="dtpValidTill" Height="24" HorizontalAlignment="Left" VerticalAlignment="Top" SelectedDate="{Binding CurrentEntity.DefaultDiscountValidTill}" SelectedDateFormat="Short"/>

        <ComboBox Grid.Row="6" Grid.Column="1" Margin="5,3,0,0" Width="190" Height="30" Name="cmbEmployeeName" ItemsSource="{Binding Employees}" DisplayMemberPath="FullName" SelectedIndex="{Binding SelecteIndex}">

        </ComboBox>

        <Custom:DataGrid Grid.Row="8" Grid.Column="0" Grid.ColumnSpan="2" ItemsSource="{Binding XYZ}" AutoGenerateColumns="False" Name="grdTestDept">
            <Custom:DataGrid.Columns>
                <Custom:DataGridTextColumn Binding="{Binding dep_id}" Width="40" Header="ID"/>
                <Custom:DataGridTextColumn Binding="{Binding dep_name}" Width="125" Header="Name"/>
                <Custom:DataGridTextColumn Binding="{Binding default_data}" Width="100" Header="Default Data"/>
            </Custom:DataGrid.Columns>
        </Custom:DataGrid>

    </Grid>

    <Grid Grid.Row="0" Grid.Column="1" Grid.RowSpan="9">

        <Grid.ColumnDefinitions>
            <ColumnDefinition Width="Auto" MinWidth="43"></ColumnDefinition>
            <ColumnDefinition Width="Auto" MinWidth="150"></ColumnDefinition>
            <ColumnDefinition Width="Auto" MinWidth="50"></ColumnDefinition>
        </Grid.ColumnDefinitions>

        <Grid.RowDefinitions>
            <RowDefinition Height="34*" ></RowDefinition>
            <RowDefinition Height="337.88*"></RowDefinition>
        </Grid.RowDefinitions>

        <TextBlock Text="Name: " Grid.Row="0" Grid.Column="0" Margin="5,4,0,0" />

        <cc:ValueEnabledCombo Grid.Column="1" x:Name="cmbfilEmployeeName" Width="150" Height="30" Margin="5,4,0,0" VerticalAlignment="Top" SelectedIndex="0"
             ItemsSource="{Binding Employees}" DisplayMemberPath="FullName" SelectedValuePath="EmployeeId" cc:ValueEnabledCombo.SelectionChanged="{Binding SelectionChangedCommand}">

        </cc:ValueEnabledCombo>

        <Button Grid.Column="2" Name="btnReport" Width="50" Content="Report" Height="28" Margin="5,4,0,0" Command="{Binding ReportCommand}" VerticalAlignment="Top" />
            <Grid Grid.Row="1"  Grid.Column="0" Grid.ColumnSpan="3">

                <Custom:DataGrid  ItemsSource="{Binding DoctorList}" AutoGenerateColumns="False" Name="grdDoctor" ScrollViewer.HorizontalScrollBarVisibility="Auto" ScrollViewer.VerticalScrollBarVisibility="Auto">
                    <Custom:DataGrid.Columns>
                        <Custom:DataGridTextColumn Binding="{Binding RefName}" Width="Auto" Header="Doctor Name"/>
                        <Custom:DataGridTextColumn Binding="{Binding EmployeeFullName}" Width="Auto" Header="Employee Name"/>
                    </Custom:DataGrid.Columns>
                </Custom:DataGrid>                    
             </Grid>
    </Grid>       
</Grid>

Kent Boogaart posted the answer here:

how can I enable scrollbars on the WPF Datagrid?

Put the DataGrid in a Grid, DockPanel, ContentControl or directly in the Window. A vertically-oriented StackPanel will give its children whatever vertical space they ask for - even if that means it is rendered out of view.

My note: It's probably best not to set the max height and width. Leave those alone and let WPF take care of the resizing for you.