Hello again,

im trying to change the text and the colour of Errormessage. 

<telerik:RadDatePicker x:Name=""" .....ErrorToolTipContent="Hello for Example">
<telerik:RadDatePicker.TooltipTemplate>
                <DataTemplate>
                    <TextBlock Text="{Binding Path=TooltipContent, ElementName=radDatePicker}"
                               FontWeight="Bold"
                               Foreground="Red" />
                </DataTemplate>
            </telerik:RadDatePicker.TooltipTemplate>
        </telerik:RadDatePicker>

But it doesnt show any Errormessage. How can I solve this problem?

Best regards
Christian

Hello Christian,

The template of the ErrorToolTip, unfortunately, cannot be changed. You can only set its Content, but not the template.
Sorry for the caused inconvenience.

Best wishes,
Konstantina
the Telerik team