System.Data.Edm.EdmEntityType: : EntityType '???' has no key defined. Define the key for this EntityType

Anyone have Fix for this?

namespace MvcApplication1.Models
{
    public class Team
    {
        [Key]
        public int TeamId { get; set; }
        [Required]
        public string Name { get; set; }
        public string City { get; set; }
        public DateTime Founded { get; set; }
    }

.... Then tried to create a TeamController !!