Metro app using Enterprise Authentication: why do I still see login prompt
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I have an WinJS metro application that I'm using to connect to a remote webservice that same domain.  I read up on the app manifest capability (well the little that is present online) and was hoping that I would be able to use the logged in users credentials to access this webservice without requiring them to login.

I'm trying to authenticate to the webservice via a post using a contentType: "application/x-www-form-urlencoded;charset='utf-8'".  This application was previously a website that would prompt the user for login credentials in the authentication step using the aforementioned post.  In the WinJS metro application I'm effectively using the same code (minor tweaks) to achieve the same result.

Has anyone had experience with Enterprise Authentication in a WinJS metro application and could better explain what types of resources I would/wouldn't have access to.  I'm hoping this isn't specific to accessing things like file shares and intranet sites.