I have created a Windows 8 grid app in Visual Studio. This app creates links to pages in a SharePoint portal, so if a user clicks a tile, it should open a web page within the app frame.
However, each time a user tries to view a page, it asks for SharePoint username and password.
How do I set the authentication to be done automatically in the app? So that when a user tries to view a page it opens it directly.
Note that in the SharePoint portal, authentication is done automatically from the Active Directory.