diff --git a/app/controllers/zipdown_controller.rb b/app/controllers/zipdown_controller.rb
index cb4ab3c7a..e57a2c59a 100644
--- a/app/controllers/zipdown_controller.rb
+++ b/app/controllers/zipdown_controller.rb
@@ -82,10 +82,10 @@ class ZipdownController < ApplicationController
     user_zip_paths = homeattaches.map do |homeattach|
       if homeattach.attachments.count > 0
         zip_homework_by_user homeattach
-        has_file = true if has_file == false
+        has_file = true unless has_file
       end
     end
-    if has_file == false
+    unless has_file
       render file: 'public/no_file_fond.html' , :layout => 'course_base'
     end
     zipping "#{Time.now.to_i}_#{bid.name}.zip", user_zip_paths, OUTPUT_FOLDER