diff --git a/app/controllers/attachments_controller.rb b/app/controllers/attachments_controller.rb
index f00cbb03d..0aec29e6a 100644
--- a/app/controllers/attachments_controller.rb
+++ b/app/controllers/attachments_controller.rb
@@ -181,7 +181,8 @@ class AttachmentsController < ApplicationController
 
     respond_to do |format|
       # modify by nwb
-      if !@attachment.container.nil? && (@attachment.container.has_attribute?(:course) ||@attachment.container.has_attribute?(:course_id) ) &&(@attachment.container.is_a?(Course) || @attachment.container.course)
+      if !@attachment.container.nil? &&
+         (@attachment.container.is_a?(Course) || ((@attachment.container.has_attribute?(:course) ||@attachment.container.has_attribute?(:course_id) )  && @attachment.container.course ) )
         if @attachment.container.is_a?(News)
           format.html { redirect_to_referer_or news_path(@attachment.container) }
         elsif @course.nil?