diff --git a/web/system.py b/web/system.py
index 75d77c4..8347718 100644
--- a/web/system.py
+++ b/web/system.py
@@ -90,7 +90,7 @@ def save_config():
         # config files, then increment version before unlocking.
         with db.locked():
             settings = db.read('settings')
-            version = settings['version'] = int(settings.get('version', 0)) + 1
+            version = settings['version'] = int(settings.get('version') or '0') + 1
 
             # Populate IP sets.
             ipsets = collections.defaultdict(set)
@@ -155,7 +155,7 @@ def save_config():
             # Print wireguard config.
             with open(output / 'etc/wireguard/wg.conf', 'w', encoding='utf-8') as f:
                 f.write(wg_intf.format(
-                    port=settings.get('wg_port', 51820),
+                    port=settings.get('wg_port') or 51820,
                     key=settings.get('wg_key')))
                 for ip, data in wireguard.items():
                     f.write(wg_peer.format(
diff --git a/web/vpn.py b/web/vpn.py
index bb09540..ce82fe4 100644
--- a/web/vpn.py
+++ b/web/vpn.py
@@ -50,7 +50,7 @@ def new():
     server_pubkey = subprocess.run([f'wg pubkey'], input=settings.get('wg_key'),
             text=True, capture_output=True, shell=True).stdout.strip()
 
-    host = ipaddress.ip_interface(settings.get('wg_net', '10.0.0.1/24'))
+    host = ipaddress.ip_interface(settings.get('wg_net') or '10.0.0.1/24')
     ip6 = None
     with db.locked():
         # Find a free address for the new key.
@@ -80,7 +80,7 @@ def new():
     # Template arguments.
     args = {
         'server': settings.get('wg_endpoint'),
-        'port': settings.get('wg_port', '51820'),
+        'port': settings.get('wg_port') or '51820',
         'server_key': server_pubkey,
         'pubkey': pubkey,
         'ip': str(ip),
@@ -88,7 +88,7 @@ def new():
         'timestamp': now,
         'name': name,
         'dns': settings.get('wg_dns') if flask.request.json.get('use_dns', True) else False,
-        'allowed_nets': settings.get('wg_allowed_nets', []),
+        'allowed_nets': settings.get('wg_allowed_nets', ''),
         'add_default': flask.request.json.get('add_default', False),
     }
     return flask.render_template('vpn/wg-fri.conf', **args)