I don't think you need the "new {area = ""}" segment
so just,
<a href="@Url.Action("Index","Home")">Dashboard</a>
if you are using areas then you need to use something like
@Url.Action("Method", "Controller", new {Area = "AreaName"})
when you load the page up you can always check where the url is pointing to by using the browser's developer tools. eg on chrome right click inspect
If the URL is as you are expecting and it is still not working then it is probably your routing that is wrong. Mine looks like this
routes.MapRoute(
name: "Default",
url: "{controller}/{action}/{id}",
defaults: new { controller = "Home", action = "Index", id = UrlParameter.Optional }
);