Good Day i have a Window in WPF defined like this

Code:
 <Window x:Class="RVI_Education.Gavigator"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        Title="Gavigator" Height="673.2" Width="1304.4">
    <Frame Name="FrameWithinGrid" >
    </Frame>
</Window>
and im using it as a start up in my app.xaml

Code:
 <Application x:Class="RVI_Education.App"
             xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
             xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
             StartupUri="Gavigator.xaml">
    <Application.Resources>
         
    </Application.Resources>
</Application>


and on Window loaded event i navigate to another Window

like this

Code:
    public Gavigator()
        {
            InitializeComponent();
            Loaded += Gavigator_Loaded;
           
        }

        void Gavigator_Loaded(object sender, RoutedEventArgs e)
        { 

          FrameWithinGrid.Navigate(new System.Uri("Splash.xaml",UriKind.RelativeOrAbsolute));

        }
when i load the Project i get an Error


'RVI_Education.Splash' root element is not valid for navigation.