ASP .net MVC调用默认控制器和操作vs设置启动页面

I am developing code on the sample ASP .net MVC template provided by VS2010. The first time I ran the code without adding anything, the index.aspx page was invoked which is expected. But for some reasons I added a login.aspx and then accidentally set that as a startup page. Now when I ran the application the default startup url look like I am developing code on the sample ASP .net MVC