Cannot convert lambda expression to type 'string' because it is not a delegate type

Cannot convert lambda expression to type 'string' because it is not a delegate type

var customers = from customer in DBContext.Customers.Include("Orders")
                select customer;

var customers = from customer in DBContext.Customers.Include(c => c.Orders)
                select customer;

Solution

Make sure you are using that namespace. Please add this namespace.

using System.Data.Entity;