Startup of Application Exception Can't find resource named

Question

Hi I am new to WPF , 

In my WPF MVVM application , before starting of application there are some conditions to check  after which homewindow screen will come other wise login screen will come . 

The code which i have written is like this -:

public App()

{

if (System.Configuration.ConfigurationManager.AppSettings.Count > 0)

{

app.MainWindow homeWindow = new app.MainWindow();

var app = new Application();

app.Run(homeWindow);

}

else

{

LoginWindow mainWindow = new LoginWindow();

var app = new Application();

app.Run(mainWindow);

}

 

 

If i run it normally like Startup URI="LoginWindow.xaml" without anycondition , loginscreen window is coming but when i am using as i have stated in the code its throwing exception, Can't find named resource . Resources are case sensitive at one of my static resource.

 

Why that exception is coming?