Entity framework, problems updating related objects

Question

I am currently working on a project using the latest version of Entity Framework and I have come across an issue which I can not seem to solve.

When it comes to up

Answer 1

Just thought I would post the link below as it really helped me understand how to update related entities.

Updating related data with the entity framework in an asp net mvc application

NOTE: I did change the logic slightly that is shown in the UpdateInstructorCourses function to suit my needs.