Im new to Expression and by accident I deleted the App.xaml file. I think this is an important file and I cannot workout how to create an equivalent.
Create a new project and copy that one.
<Application x:Class="Test.App" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" StartupUri="Window1.xaml"> <Application.Resources> </Application.Resources> </Application>
Unless you had Application Resources defined, then you may be in trouble.
Might be a good argument for Source Control.