diff --git a/app/controllers/boards_controller.rb b/app/controllers/boards_controller.rb
index e0bd9582d..a692acc12 100644
--- a/app/controllers/boards_controller.rb
+++ b/app/controllers/boards_controller.rb
@@ -140,7 +140,11 @@ private
   end
 
   def find_board_if_available
-    @board = @project.boards.find(params[:id]) if params[:id]
+    if @project
+      @board = @project.boards.find(params[:id]) if params[:id]
+    elsif @course
+      @board = @course.boards.find(params[:id]) if params[:id]
+    end
   rescue ActiveRecord::RecordNotFound
     render_404
   end
diff --git a/app/controllers/messages_controller.rb b/app/controllers/messages_controller.rb
index 2915ff8f8..90e0d937c 100644
--- a/app/controllers/messages_controller.rb
+++ b/app/controllers/messages_controller.rb
@@ -112,10 +112,19 @@ class MessagesController < ApplicationController
     (render_403; return false) unless @message.destroyable_by?(User.current)
     r = @message.to_param
     @message.destroy
-    if @message.parent
-      redirect_to board_message_path(@board, @message.parent, :r => r)
-    else
-      redirect_to project_board_path(@project, @board)
+    # modify by nwb
+    if @project
+      if @message.parent
+        redirect_to board_message_path(@board, @message.parent, :r => r)
+      else
+        redirect_to project_board_path(@project, @board)
+      end
+    elsif @course
+      if @message.parent
+        redirect_to board_message_path(@board, @message.parent, :r => r)
+      else
+        redirect_to course_board_path(@course, @board)
+      end
     end
   end