Red border remains on the TextBox even after the data input is valid

Question

I am writing an app using WPF, WPF Application Framework and MahApps.Metro. I have validation enabled for a data entry window like this:

Answer 1

I've come across this before, when it happened to me I had to perform a data change during initialize and ContentRendered. Cause I had the items actually bound.

Another thing I saw awhile ago on Stack Overflow was an issue that happened here that also caused something similar.

<Setter Property="Validation.ErrorTemplate">
    <Setter.Value>
        <ControlTemplate>
            <ControlTemplate.Resources>
                <BooleanToVisibilityConverter x:Key="converter" />
        </ControlTemplate.Resources>
            <DockPanel LastChildFill="True">
                <Border 
                    BorderThickness="1"
                    BorderBrush="Red"
                    Visibility="{Binding ElementName=placeholder, Mode=OneWay, Path=AdornedElement.IsVisible, Converter={StaticResource converter}}">
                    <AdornedElementPlaceholder x:Name="placeholder" />
                </Border>
             </DockPanel>
         </ControlTemplate>
    </Setter.Value>
</Setter>

That was my encounter, if that doesn't help I'll attempt to recreate the issue and fix as well. See if I can help you out a little better then describing how I fixed it. But hopefully one of those two suggestions helps you out.

Just let me know, hope it helps.