diff --git a/usr/lib/python3.8/vmmgr/wsgiapp.py b/usr/lib/python3.8/vmmgr/wsgiapp.py
index c717fc4..ac3def0 100644
--- a/usr/lib/python3.8/vmmgr/wsgiapp.py
+++ b/usr/lib/python3.8/vmmgr/wsgiapp.py
@@ -26,6 +26,7 @@ logging.basicConfig(level=logging.WARNING)
 
 class WSGIApp:
     def __init__(self):
+        self.demo = config.get_common().get('demo')
         self.queue = ActionQueue()
         self.jinja_env = Environment(loader=FileSystemLoader('/usr/share/vmmgr/templates'), autoescape=True, lstrip_blocks=True, trim_blocks=True)
         self.url_map = Map((
@@ -289,6 +290,9 @@ class WSGIApp:
         return self.render_html('setup-remote.html', request, authorized_keys=authorized_keys, wg_conf=wg_conf, message=message)
 
     def update_host_action(self, request):
+        # Do nothing in demo
+        if self.demo:
+            return self.render_json({'error': request.session.lang.not_available_in_demo()})
         # Update domain and port, then restart nginx
         domain = request.form['domain']
         port = request.form['port']
@@ -339,6 +343,9 @@ class WSGIApp:
         return self.render_json({'ok': request.session.lang.http_hosts_ok(port)})
 
     def update_cert_action(self, request):
+        # Do nothing in demo
+        if self.demo:
+            return self.render_json({'error': request.session.lang.not_available_in_demo()})
         # Update certificate - either request via Let's Encrypt or manually upload files
         if request.form['method'] == 'selfsigned':
             vmmgr.create_selfsigned_cert()
@@ -361,6 +368,10 @@ class WSGIApp:
         return self.render_json({'ok': request.session.lang.cert_installed(url, url)})
 
     def update_common_action(self, request):
+        # Do nothing in demo
+        if self.demo:
+            request.session['msg'] = f'common:error:{request.session.lang.not_available_in_demo()}'
+            return redirect('/setup-apps')
         # Update common settings shared between apps - admin e-mail address, Google Maps API key
         email = request.form['email']
         if not validator.is_valid_email(email):
@@ -371,6 +382,10 @@ class WSGIApp:
         return redirect('/setup-apps')
 
     def update_repo_action(self, request):
+        # Do nothing in demo
+        if self.demo:
+            request.session['msg'] = f'repo:error:{request.session.lang.not_available_in_demo()}'
+            return redirect('/setup-apps')
         # Update repository URL and credentials
         url = request.form['repourl']
         if not validator.is_valid_repo_url(url):
@@ -428,6 +443,9 @@ class WSGIApp:
         return self.render_json({'ok': self.render_setup_apps_table(request)})
 
     def update_password_action(self, request):
+        # Do nothing in demo
+        if self.demo:
+            return self.render_json({'error': request.session.lang.not_available_in_demo()})
         # Updates password for both HDD encryption (LUKS-on-LVM) and web interface admin account
         if request.form['newpassword'] != request.form['newpassword2']:
             return self.render_json({'error': request.session.lang.password_mismatch()})
@@ -441,18 +459,27 @@ class WSGIApp:
         return self.render_json({'ok': request.session.lang.password_changed()})
 
     def reboot_vm_action(self, request):
+        # Do nothing in demo
+        if self.demo:
+            return self.render_json({'error': request.session.lang.not_available_in_demo()})
         # Reboots VM
         response = self.render_json({'ok': request.session.lang.reboot_initiated()})
         response.call_on_close(vmmgr.reboot_vm)
         return response
 
     def shutdown_vm_action(self, request):
+        # Do nothing in demo
+        if self.demo:
+            return self.render_json({'error': request.session.lang.not_available_in_demo()})
         # Shuts down VM
         response = self.render_json({'ok': request.session.lang.shutdown_initiated()})
         response.call_on_close(vmmgr.shutdown_vm)
         return response
 
     def update_ssh_keys_action(self, request):
+        # Do nothing in demo
+        if self.demo:
+            return self.render_json({'error': request.session.lang.not_available_in_demo()})
         # Update authorized_keys file
         remote.set_authorized_keys(request.form['ssh-keys'].replace('\r', ''))
         request.session['msg'] = f'ssh:info:{request.session.lang.ssh_keys_installed()}'
diff --git a/usr/lib/python3.8/vmmgr/wsgilang.py b/usr/lib/python3.8/vmmgr/wsgilang.py
index a7a26ee..7aa8011 100644
--- a/usr/lib/python3.8/vmmgr/wsgilang.py
+++ b/usr/lib/python3.8/vmmgr/wsgilang.py
@@ -54,6 +54,7 @@ class WSGILang:
         'action_update': 'Aktualizovat',
         'ssh_keys_installed': 'SSH klíče byly úspěšně změněny.',
         'vpn_updated': 'Nastavení VPN bylo úspěšně změněno.',
+        'not_available_in_demo': 'Tato funkce není v demo verzi povolena',
     }
 
     def __getattr__(self, key):
diff --git a/usr/share/vmmgr/static/js/admin.js b/usr/share/vmmgr/static/js/admin.js
index c339f71..6a1abd1 100644
--- a/usr/share/vmmgr/static/js/admin.js
+++ b/usr/share/vmmgr/static/js/admin.js
@@ -205,7 +205,11 @@ function update_password() {
 
 function _do_vm(action) {
     $.get('/'+action+'-vm', function(data) {
-        $('#vm-message').attr('class','info').html(data.ok).show();
+        if (data.error) {
+            $('#vm-message').attr('class','error').html(data.error).show();
+        } else {
+            $('#vm-message').attr('class','info').html(data.ok).show();
+        }
     }).fail(lost_connection_alert);
 }