MVC4 Scaffolding Add Controller gives error “Unable to retrieve metadata…”

By trial and error I found the line of code (it’s the DbContext ctor) that is causing the error: public class MyThingDb : DbContext { // If I comment this constructor out the scaffolding works public MyThingDb() : base(“DefaultConnection”) { } public DbSet<MyThing> Things{ get; set; } } WTF?