diff --git a/spec/models/channel/email_parser_spec.rb b/spec/models/channel/email_parser_spec.rb
index 26469db3d..4b8963f8f 100644
--- a/spec/models/channel/email_parser_spec.rb
+++ b/spec/models/channel/email_parser_spec.rb
@@ -91,12 +91,62 @@ RSpec.describe Channel::EmailParser, type: :model do
       let(:ticket) { create(:ticket) }
 
       context 'when email subject contains ticket reference' do
-        let(:raw_mail)   { File.read(mail_file).sub(/(?<=^Subject: ).*$/, ticket_ref) }
+        let(:raw_mail) { File.read(mail_file).sub(/(?<=^Subject: ).*$/, ticket_ref) }
 
         it 'adds message to ticket' do
           expect { described_class.new.process({}, raw_mail) }
             .to change { ticket.articles.length }
         end
+
+        context 'and ticket is closed' do
+          before { ticket.update(state: Ticket::State.find_by(name: 'closed')) }
+
+          it 'adds message to ticket' do
+            expect { described_class.new.process({}, raw_mail) }
+              .to change { ticket.articles.length }
+          end
+        end
+
+        context 'but ticket group’s #follow_up_possible attribute is "new_ticket"' do
+          before { ticket.group.update(follow_up_possible: 'new_ticket') }
+
+          context 'and ticket is open' do
+            it 'still adds message to ticket' do
+              expect { described_class.new.process({}, raw_mail) }
+                .to change { ticket.articles.length }
+            end
+          end
+
+          context 'and ticket is closed' do
+            before { ticket.update(state: Ticket::State.find_by(name: 'closed')) }
+
+            it 'creates a new ticket' do
+              expect { described_class.new.process({}, raw_mail) }
+                .to change { Ticket.count }.by(1)
+                .and not_change { ticket.articles.length }
+            end
+          end
+
+          context 'and ticket is merged' do
+            before { ticket.update(state: Ticket::State.find_by(name: 'merged')) }
+
+            it 'creates a new ticket' do
+              expect { described_class.new.process({}, raw_mail) }
+                .to change { Ticket.count }.by(1)
+                .and not_change { ticket.articles.length }
+            end
+          end
+
+          context 'and ticket is removed' do
+            before { ticket.update(state: Ticket::State.find_by(name: 'removed')) }
+
+            it 'creates a new ticket' do
+              expect { described_class.new.process({}, raw_mail) }
+                .to change { Ticket.count }.by(1)
+                .and not_change { ticket.articles.length }
+            end
+          end
+        end
       end
 
       context 'when configured to search body' do
diff --git a/test/unit/email_process_follow_up_possible_test.rb b/test/unit/email_process_follow_up_possible_test.rb
deleted file mode 100644
index ed05bf634..000000000
--- a/test/unit/email_process_follow_up_possible_test.rb
+++ /dev/null
@@ -1,71 +0,0 @@
-require 'test_helper'
-
-class EmailProcessFollowUpPossibleTest < ActiveSupport::TestCase
-
-  test 'process with follow up possible check' do
-
-    users_group = Group.lookup(name: 'Users')
-
-    ticket = Ticket.create(
-      title:         'follow up check',
-      group:         users_group,
-      customer_id:   2,
-      state:         Ticket::State.lookup(name: 'new'),
-      priority:      Ticket::Priority.lookup(name: '2 normal'),
-      updated_by_id: 1,
-      created_by_id: 1,
-    )
-    article = Ticket::Article.create(
-      ticket_id:     ticket.id,
-      from:          'some_sender@example.com',
-      to:            'some_recipient@example.com',
-      subject:       'follow up check',
-      message_id:    '<20150830145601.30.608882@edenhofer.zammad.com>',
-      body:          'some message article',
-      internal:      false,
-      sender:        Ticket::Article::Sender.lookup(name: 'Agent'),
-      type:          Ticket::Article::Type.lookup(name: 'email'),
-      updated_by_id: 1,
-      created_by_id: 1,
-    )
-
-    follow_up_raw = "From: me@example.com
-To: customer@example.com
-Subject: #{ticket.subject_build('some new subject')}
-
-Some Text"
-
-    users_group.update!('follow_up_possible' => 'new_ticket')
-
-    travel 1.second
-    ticket_p, article_p, user_p = Channel::EmailParser.new.process({}, follow_up_raw)
-    assert_equal(ticket.id, ticket_p.id)
-    assert_equal('follow up check', ticket_p.title)
-    assert_match('some new subject', article_p.subject)
-
-    # close ticket
-    ticket.state = Ticket::State.find_by(name: 'closed')
-    ticket.save!
-
-    follow_up_raw = "From: me@example.com
-To: customer@example.com
-Subject: #{ticket.subject_build('some new subject2')}
-
-Some Text"
-
-    travel 1.second
-    ticket_p, article_p, user_p = Channel::EmailParser.new.process({}, follow_up_raw)
-    assert_not_equal(ticket.id, ticket_p.id)
-    assert_equal('some new subject2', ticket_p.title)
-    assert_equal('some new subject2', article_p.subject)
-
-    users_group.update!('follow_up_possible' => 'yes')
-
-    travel 1.second
-    ticket_p, article_p, user_p = Channel::EmailParser.new.process({}, follow_up_raw)
-    assert_equal(ticket.id, ticket_p.id)
-    assert_equal('follow up check', ticket_p.title)
-    assert_match('some new subject', article_p.subject)
-    travel_back
-  end
-end