diff --git a/app/controllers/files_controller.rb b/app/controllers/files_controller.rb
index 683d35da2..0299fdf7d 100644
--- a/app/controllers/files_controller.rb
+++ b/app/controllers/files_controller.rb
@@ -272,6 +272,8 @@ class FilesController < ApplicationController
       @old_attachment.unified_setting = @unified_setting
       if @unified_setting == 0
         attachment_group_setting @old_attachment, params[:group_settings]
+      else
+        @old_attachment.attachment_group_settings.destroy_all
       end
 
       if params[:description] && !params[:description].strip.blank? && params[:description] != @old_attachment.description
diff --git a/app/views/files/show.json.jbuilder b/app/views/files/show.json.jbuilder
index 71359ccfd..941e66619 100644
--- a/app/views/files/show.json.jbuilder
+++ b/app/views/files/show.json.jbuilder
@@ -1,3 +1,3 @@
 json.partial! 'attachments/attachment', attachment: @file
-# json.partial! "files/course_groups", attachment_group_settings: @file.attachment_group_settings
+json.partial! "files/course_groups", attachment_group_settings: @file.attachment_group_settings
 json.partial! "attachment_histories/list", attachment_histories: @attachment_histories
\ No newline at end of file