Here is my function: def list @fr_pages, @frs = paginate :frs, :per_page => 10 if Fr.find(params[:id]) == "" flash[:notice] = 'Veuillez rentrer une nouvelle fois votre matricule svp =)' redirect_to :controller => 'hello', :action => 'index' end @mfr = Fr.find(params[:id]) end When I call this url: http://site.com/main/action/list ive got this error: Couldn't find Fr without an ID. Does anyone know why redirect_to does not work please ?