diff --git a/app/jobs/scheduled/purge_unactivated.rb b/app/jobs/scheduled/purge_unactivated.rb
index 992b1bddc88..98798720552 100644
--- a/app/jobs/scheduled/purge_unactivated.rb
+++ b/app/jobs/scheduled/purge_unactivated.rb
@@ -1,5 +1,5 @@
 module Jobs
-  class PurgeUnactived < Jobs::Scheduled
+  class PurgeUnactivated < Jobs::Scheduled
     every 1.day
 
     def execute(args)
diff --git a/app/models/user.rb b/app/models/user.rb
index 58709059dad..0168a7b985b 100644
--- a/app/models/user.rb
+++ b/app/models/user.rb
@@ -1222,7 +1222,9 @@ class User < ActiveRecord::Base
       .where(active: false)
       .where("created_at < ?", SiteSetting.purge_unactivated_users_grace_period_days.days.ago)
       .where("NOT admin AND NOT moderator")
-      .where("NOT EXISTS (SELECT 1 FROM topic_allowed_users WHERE user_id = users.id LIMIT 1)")
+      .where("NOT EXISTS
+              (SELECT 1 FROM topic_allowed_users tu JOIN topics t ON t.id = tu.topic_id AND t.user_id > 0 WHERE tu.user_id = users.id)
+            ")
       .limit(200)
       .find_each do |user|
       begin
diff --git a/spec/models/user_spec.rb b/spec/models/user_spec.rb
index 4e9f4ba9b07..6a34ecae5c0 100644
--- a/spec/models/user_spec.rb
+++ b/spec/models/user_spec.rb
@@ -1257,26 +1257,34 @@ describe User do
     let!(:user) { Fabricate(:user) }
     let!(:unactivated) { Fabricate(:user, active: false) }
     let!(:unactivated_old) { Fabricate(:user, active: false, created_at: 1.month.ago) }
-    let!(:unactivated_old_with_pm) { Fabricate(:user, active: false, created_at: 2.months.ago) }
+    let!(:unactivated_old_with_system_pm) { Fabricate(:user, active: false, created_at: 2.months.ago) }
+    let!(:unactivated_old_with_human_pm) { Fabricate(:user, active: false, created_at: 2.months.ago) }
 
     before do
       PostCreator.new(Discourse.system_user,
         title: "Welcome to our Discourse",
         raw: "This is a welcome message",
         archetype: Archetype.private_message,
-        target_usernames: [unactivated_old_with_pm.username],
+        target_usernames: [unactivated_old_with_system_pm.username],
+      ).create
+
+      PostCreator.new(user,
+        title: "Welcome to our Discourse",
+        raw: "This is a welcome message",
+        archetype: Archetype.private_message,
+        target_usernames: [unactivated_old_with_human_pm.username],
       ).create
     end
 
     it 'should only remove old, unactivated users' do
       User.purge_unactivated
-      expect(User.real.all).to match_array([user, unactivated, unactivated_old_with_pm])
+      expect(User.real.all).to match_array([user, unactivated, unactivated_old_with_human_pm])
     end
 
     it "does nothing if purge_unactivated_users_grace_period_days is 0" do
       SiteSetting.purge_unactivated_users_grace_period_days = 0
       User.purge_unactivated
-      expect(User.real.all).to match_array([user, unactivated, unactivated_old, unactivated_old_with_pm])
+      expect(User.real.all).to match_array([user, unactivated, unactivated_old, unactivated_old_with_system_pm, unactivated_old_with_human_pm])
     end
   end