This is about ConnectionStrings / ASP.NET MVC with Visual Studio 2012 ultimate & SQL Server Express 2012.
Following up with this tutorial here: http://www.asp.ne
I had the same issue. I believe the difference is in the Integrated Security setting. I have SQLExpress installed and found my Movies database in there using MS SQL Server Management Studio.
Check out this response for a better explanation. Difference between Integrated Security = True and Integrated Security = SSPI