diff --git a/plinth/modules/apache/__init__.py b/plinth/modules/apache/__init__.py
index 988d44ab0..2f943fc4a 100644
--- a/plinth/modules/apache/__init__.py
+++ b/plinth/modules/apache/__init__.py
@@ -27,7 +27,7 @@ is_essential = True
 managed_packages = ['apache2', 'libapache2-mod-gnutls', 'libapache2-mod-php']
 
 
-def setup(helper, old_version=False):
+def setup(helper, old_version=None):
     """Configure the module."""
     helper.install(managed_packages)
     actions.superuser_run('apache', ['setup'])
diff --git a/plinth/modules/avahi/__init__.py b/plinth/modules/avahi/__init__.py
index 50de614fd..9a1703516 100644
--- a/plinth/modules/avahi/__init__.py
+++ b/plinth/modules/avahi/__init__.py
@@ -64,7 +64,7 @@ def init():
                                      is_external=False)
 
 
-def setup(helper, old_version=False):
+def setup(helper, old_version=None):
     """Install and configure the module."""
     helper.install(managed_packages)
     # Reload avahi-daemon now that first-run does not reboot. After performing
diff --git a/plinth/modules/ssh/__init__.py b/plinth/modules/ssh/__init__.py
index 9ffe2049d..d37da3a83 100644
--- a/plinth/modules/ssh/__init__.py
+++ b/plinth/modules/ssh/__init__.py
@@ -55,7 +55,7 @@ def init():
         managed_services[0], name, ports=['ssh'], is_external=True)
 
 
-def setup(helper, old_version=False):
+def setup(helper, old_version=None):
     """Configure the module."""
     actions.superuser_run('ssh', ['setup'])