The view ‘Index’ or its master was not found.

What you need to do is set a token to your area name:

for instance:

context.MapRoute(
        "SomeArea_default",
        "SomeArea/{controller}/{action}/{id}",
        new { controller = "SomeController", action = "Index", id = UrlParameter.Optional }
    ).DataTokens.Add("area", "YOURAREANAME");