The EntitySet name 'X' from the object's EntityKey does not match the expected EntitySet name, 'Y'.

Go this one tonight, and caused me some grief for a bit.

Basically, I have a foreign key mapping to my company into my user profile and I was trying to perform an update on the foreign key.  Here's my user profile:


    public class UserProfile
    {
        [Key]
        [DatabaseGeneratedAttribute(DatabaseGeneratedOption.Identity)]
        public int UserId { get; set; }
        public string UserName { get; set; }
        public string EmailAddress { get; set; }
        public string Firstname { get; set; }
        public string Surname { get; set; }

        [ForeignKey("CompanyId")]
        public Company Company { get; set; }

        public int CompanyId { get; set; }
    }

if you want to update the company you have to set the company to null but set the foreign key seperately :


using (var context = new UsersContext())
            {
                profile.UserName = userViewModel.UserName;
                profile.EmailAddress = userViewModel.EmailAddress;
                profile.Firstname = userViewModel.FirstName;
                profile.Surname = userViewModel.Surname;
                profile.Company = null;
                profile.CompanyId = userViewModel.CompanyId;
                //profile.Company = userViewModel.Companies.FirstOrDefault(c => c.Id == userViewModel.CompanyId);
                context.Entry(profile).State = EntityState.Modified;
                context.SaveChanges();
            }

now it works !