Hi, I have a many-to-many relationship via a join table. When I attempt to set the values (i.e. the relationship) in the join table via the Rails console I get the following error, does anyone know what could be wrong? Thanks. Note: I have set attr_accessible -- see Grade model below. ActiveModel::MassAssignmentSecurity::Error: Can''t mass-assign protected attributes: id, grade_salary_attributes_attributes In the Rails console I execute: grade = Grade.find(:first) params = {:grade => { :id => 1, :grade_salary_attributes_attributes => { :id => 1, :grade_id => 1, :salary_attribute_id => 2 }}} grade.update_attributes(params[:grade]) Below are the 3 models: **Grade Model** class Grade < ActiveRecord::Base has_many :grade_salary_attributes has_many :salary_attributes, :through => :grade_salary_attributes accepts_nested_attributes_for :grade_salary_attributes, :reject_if => lambda {|attributed| attributed[''grade_id''].nil? || attributed[''salary_attribute_id''].nil?} attr_accessible :description, :title, :grade_salary_attributes_attributes end **Salary Attribute Model** class SalaryAttribute < ActiveRecord::Base has_many :grade_salary_attributes has_many :grades, :through => :grade_salary_attributes attr_accessible :description, :title end **Grade Salary Attribute (Join) Model** class GradeSalaryAttribute < ActiveRecord::Base belongs_to :grade belongs_to :salary_attribute attr_accessible :grade_id, :salary_attribute_id end -- Posted via http://www.ruby-forum.com/. -- You received this message because you are subscribed to the Google Groups "Ruby on Rails: Talk" group. To post to this group, send email to rubyonrails-talk-/JYPxA39Uh5TLH3MbocFF+G/Ez6ZCGd0@public.gmane.org To unsubscribe from this group, send email to rubyonrails-talk+unsubscribe-/JYPxA39Uh5TLH3MbocFF+G/Ez6ZCGd0@public.gmane.org For more options, visit https://groups.google.com/groups/opt_out.