I'm trying to upgrade a project from EF 4.3.1 to EF 6.0
The template uses
I have solved the problem. It is because you've upgraded to EF 6.X from EF 5.X your edmx is still on the old legacy generation strategy.
What you need:
Update all projects using Nuget to EF 6 release
After installing 1 of these extensions you want to backup your edmx and designer files (or use source control). Restart Visual Studio.
After restarting Visual Studio you want to go into your project and:
This gives you your
ObjectContext derived context as well as everything matching the newer EF 6.0 namespaces.