diff --git a/app/models/attachment.rb b/app/models/attachment.rb
index 1e477ed04..4a6580a7a 100644
--- a/app/models/attachment.rb
+++ b/app/models/attachment.rb
@@ -259,11 +259,12 @@ class Attachment < ActiveRecord::Base
   end
 
   def office_conver
+    return unless %w(Project Course).included? (self.container_type)
     saved_path = File.join(Rails.root, "files", "convered_office")
     unless Dir.exist?(saved_path)
       Dir.mkdir(saved_path)
     end
-    convered_file = File.join(saved_path, self.disk_filename + ".html")
+    convered_file = File.join(saved_path, self.disk_filename + ".pdf")
     OfficeConverTask.new.conver(self.diskfile, convered_file)
   end