diff --git a/app/models/forum_topic.rb b/app/models/forum_topic.rb
index 4a4acf150..db0451fca 100644
--- a/app/models/forum_topic.rb
+++ b/app/models/forum_topic.rb
@@ -144,6 +144,8 @@ class ForumTopic < ActiveRecord::Base
     topic = query.first
     if topic
       CurrentUser.user.update_attribute(:last_forum_read_at, topic.updated_at)
+    else
+      CurrentUser.user.update_attribute(:last_forum_read_at, Time.now)
     end
   end
 
diff --git a/test/unit/forum_topic_test.rb b/test/unit/forum_topic_test.rb
index d549f1928..ea7a278da 100644
--- a/test/unit/forum_topic_test.rb
+++ b/test/unit/forum_topic_test.rb
@@ -38,6 +38,20 @@ class ForumTopicTest < ActiveSupport::TestCase
           @user.reload
           assert_equal(@topics[1].updated_at.to_i, @user.last_forum_read_at.to_i)
         end
+
+        context "when all topics have been read" do
+          setup do
+            @read_forum_topic_ids = ForumTopic.all.map(&:id)
+            @timestamp = Time.now
+            Time.stubs(:now).returns(@timestamp)
+          end
+
+          should "return the current time" do
+            @topic.update_last_forum_read_at(@read_forum_topic_ids)
+            @user.reload
+            assert_equal(@timestamp.to_i, @user.last_forum_read_at.to_i)
+          end
+        end
       end
 
       context "when the user's last_forum_read_at is 2 days from now" do