Scroll Bar get disappear when change the display setting

[Ritesh]

Hi Experts,

I am using Telerik.Windows.Controls.GridView , version - 2011.3.1220.40.

I am having problem with scroll bar when I change my machine's display setting from 100% to 125%.

Initially scroll bar appears on the screen, but when I scroll down to bottom and try to scroll more (as it has more rows), scroll bar gets disappear.
I have attached screenshot. Also I have attached Grid Control we have used.

here is the grid control I have used-

<telerik:RadGridView x:Name="xyzResultsGridView"
                                Controls:StyleManager.Theme="Office_Blue"
                                AutomationProperties.AutomationId="xyzResultsGridView"
                                AutoGenerateColumns="False"
                                AutoExpandGroups="True"
                                CanUserFreezeColumns="False"
                                AllowDrop="False"
                                CanUserDeleteRows="False"
                                ActionOnLostFocus="None"
                                AreRowDetailsFrozen="True"
                                CanUserInsertRows="False"
                                ClipToBounds="True"
                                IsScrolling="False"
                                UseLayoutRounding="True"
                                SelectionMode="Extended"
                                ClipboardPasteMode="Default"
                                IsReadOnly="True"
                                IsFilteringAllowed="False"
                                VirtualizingStackPanel.IsVirtualizing="True"
                                VirtualizingStackPanel.VirtualizationMode="Recycling"
                                MaxWidth="{Binding RelativeSource={RelativeSource FindAncestor, AncestorType={x:Type Grid}}, Path=ActualWidth}"
                                Focusable="False"
                            >

                <telerik:RadGridView.RowStyle>
                        <Style TargetType="GridView:GridViewRow">
                            <Setter Property="Foreground" Value="{Binding Converter={StaticResource RowToColorConverter},ConverterParameter=.}">
                            </Setter>
                            <Setter Property="FontWeight" Value="{Binding Converter={StaticResource RowToFontWeightConverter},ConverterParameter=.}">
                            </Setter>
                        </Style>
                    </telerik:RadGridView.RowStyle>

                    <Navigation:RadContextMenu.ContextMenu>
                    <Navigation:RadContextMenu x:Name="xyzResultsGridContextMenu" Opened="xyzResultsGridContextMenu_Opened"
                                               ItemClick="xyzResultsGridViewContextMenuItemClick"
                                               ItemContainerStyle="{StaticResource EnableStyle}"
                                               ItemTemplate="{StaticResource MenuItemTemplate}">
                    </Navigation:RadContextMenu>
                    </Navigation:RadContextMenu.ContextMenu>
                <telerik:RadGridView.GroupHeaderTemplate>
                    <DataTemplate>
                        <Grid>
                            <Grid.ColumnDefinitions>
                                <ColumnDefinition/>
                                <ColumnDefinition/>
                                <ColumnDefinition/>
                                <ColumnDefinition/>
                            </Grid.ColumnDefinitions>
                            <TextBlock Text ="{Binding GroupDescriptor.Column.Header}" Margin="1,0,0,0" Grid.Column="0" />
                            <TextBlock Text=": " Margin="1,0,0,0" Grid.Column="1"/>
                            <TextBlock Text= "{Binding Header}" Margin="1,0,0,0" Grid.Column="2" />
                        </Grid>
                    </DataTemplate>
                </telerik:RadGridView.GroupHeaderTemplate>
            </telerik:RadGridView>

Can you please help me ?
Thanks,
Ritesh