I got following setup:
WPF_Application.exe
and
a DLL that contains a WinForms Window and an WPF Window.
The \'WPF_Application.exe\' calls th
Make sure you only have one Application defined in XAML.
Visual studio creates an App.xaml
when making a new WPF solution, if you have created a new .xaml file with the
tag, this will cause this error and the solution will build but fail at runtime.
Delete the duplicate application and use Window
or UserControl
to have multiple windows.