Ignore URL in Silverlight 4

I have a Silverlight Business Application, and I have the login Window as first window. After that, the application loads the MainPage.xaml, but when there is somet开发者_StackOverflow社区hing on URL, the application loads the page from the URL... How can I ignore the URL???, because I need that my application goes always to MainPage after login...

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Did you try to redirect after a successful login?

 this.NavigationService.Navigate(new Uri("/Home", UriKind.Relative));