diff --git a/CB/Core.py b/CB/Core.py
index 854cd6e..43d1f31 100644
--- a/CB/Core.py
+++ b/CB/Core.py
@@ -513,6 +513,9 @@ def find_orphans(self):
         return orphanedaddon, orphaneconfig
 
     def search(self, query):
+        if self.config['WAAAPIKey'] == '':
+            raise RuntimeError('This feature requires the Wago Addons API key.\n'
+                               'It can be obtained here: https://addons.wago.io/patreon')
         results = []
         payload = requests.get(f'https://addons.wago.io/api/external/addons/_search?query={quote_plus(query.strip())}'
                                f'&game_version={self.clientType}', headers=HEADERS,
@@ -546,6 +549,9 @@ def create_reg(self):
                           '@="\\"' + os.path.abspath(sys.executable).replace('\\', '\\\\') + '\\" \\"%1\\""')
 
     def parse_wagoapp_payload(self, url):
+        if self.config['WAAAPIKey'] == '':
+            raise RuntimeError('This feature requires the Wago Addons API key.\n'
+                               'It can be obtained here: https://addons.wago.io/patreon')
         projectid = url.replace('wago-app://addons/', '')
         payload = requests.get(f'https://addons.wago.io/api/external/addons/{projectid}?game_version='
                                f'{self.clientType}', headers=HEADERS,
@@ -618,6 +624,9 @@ def detect_accounts(self):
 
     # noinspection PyTypeChecker
     def detect_addons(self):
+        if self.config['WAAAPIKey'] == '':
+            raise RuntimeError('This feature requires the Wago Addons API key.\n'
+                               'It can be obtained here: https://addons.wago.io/patreon')
         names = []
         namesinstalled = []
         slugs = []
diff --git a/CB/WagoAddons.py b/CB/WagoAddons.py
index f4f791e..2c7345e 100644
--- a/CB/WagoAddons.py
+++ b/CB/WagoAddons.py
@@ -20,6 +20,9 @@ def __init__(self, url, checkcache, clienttype, allowdev, apikey):
             self.payload['display_name'] = self.payload['name']
             self.payload['recent_release'] = self.payload['recent_releases']
         else:
+            if self.apiKey == '':
+                raise RuntimeError(f'{url}\nThe Wago Addons API key is missing. '
+                                   f'It can be obtained here: https://addons.wago.io/patreon')
             try:
                 self.payload = requests.get(f'https://addons.wago.io/api/external/addons/{project}?game_version='
                                             f'{self.clientType}', headers=HEADERS, auth=APIAuth('Bearer', self.apiKey),
diff --git a/CB/__init__.py b/CB/__init__.py
index 32cbeb6..4db2879 100644
--- a/CB/__init__.py
+++ b/CB/__init__.py
@@ -1,7 +1,7 @@
 import requests
 from rich.terminal_theme import TerminalTheme
 
-__version__ = '4.2.0'
+__version__ = '4.2.1'
 __license__ = 'GPLv3'
 __copyright__ = '2019-2022, Paweł Jastrzębski <pawelj@iosphe.re>'
 __docformat__ = 'restructuredtext en'