diff --git a/README.md b/README.md
index 81695a4..e4d4099 100644
--- a/README.md
+++ b/README.md
@@ -30,6 +30,6 @@ Szkielet komponentu Joomla 6 do gromadzenia pytań testowych.
 
 ## Instalacja
 
-W Joomla wybierz **System → Install → Install from Folder** i wskaż ten katalog. Manifestem instalacyjnym jest `com_testquestions.xml` (wersja 1.42.6).
+W Joomla wybierz **System → Install → Install from Folder** i wskaż ten katalog. Manifestem instalacyjnym jest `com_testquestions.xml` (wersja 1.42.7).
 
 Po instalacji komponent jest dostępny w panelu administratora jako **Pytania testowe**.
diff --git a/administrator/components/com_testquestions/sql/updates/mysql/1.42.7.sql b/administrator/components/com_testquestions/sql/updates/mysql/1.42.7.sql
new file mode 100644
index 0000000..ebf5489
--- /dev/null
+++ b/administrator/components/com_testquestions/sql/updates/mysql/1.42.7.sql
@@ -0,0 +1 @@
+-- No database changes required for version 1.42.7.
diff --git a/administrator/components/com_testquestions/src/Controller/ResultController.php b/administrator/components/com_testquestions/src/Controller/ResultController.php
index ed457f7..6ff6064 100644
--- a/administrator/components/com_testquestions/src/Controller/ResultController.php
+++ b/administrator/components/com_testquestions/src/Controller/ResultController.php
@@ -47,9 +47,12 @@ class ResultController extends BaseController
         try {
             $this->getModel('Result')->evaluateWithAi($id, $questionId);
         } catch (\Throwable $error) {
-            $message = $error->getMessage() === 'AI_NOT_CONFIGURED'
-                ? Text::_('COM_TESTQUESTIONS_AI_NOT_CONFIGURED')
-                : Text::sprintf('COM_TESTQUESTIONS_AI_ERROR', $error->getMessage());
+            $errorMessage = $error->getMessage();
+            $message = str_starts_with($errorMessage, 'AI_KEY_EMPTY|')
+                ? 'Diagnostyka konfiguracji AI (1.42.7): ' . substr($errorMessage, strlen('AI_KEY_EMPTY|'))
+                : ($errorMessage === 'AI_NOT_CONFIGURED'
+                    ? Text::_('COM_TESTQUESTIONS_AI_NOT_CONFIGURED')
+                    : Text::sprintf('COM_TESTQUESTIONS_AI_ERROR', $errorMessage));
             $type = 'error';
         }
 
diff --git a/administrator/components/com_testquestions/src/Model/ResultModel.php b/administrator/components/com_testquestions/src/Model/ResultModel.php
index 69efeea..84874d7 100644
--- a/administrator/components/com_testquestions/src/Model/ResultModel.php
+++ b/administrator/components/com_testquestions/src/Model/ResultModel.php
@@ -93,6 +93,7 @@ class ResultModel extends BaseDatabaseModel
         $params = ComponentHelper::getParams('com_testquestions');
         $provider = trim((string) $params->get('ai_provider', 'openai'));
         $apiKey = trim((string) $params->get('ai_api_key', ''));
+        $componentKeyLength = mb_strlen($apiKey);
 
         // Odczytaj zapisane parametry bezpośrednio z bazy. Dzięki temu nie użyjemy
         // nieaktualnej wartości z pamięci ComponentHelper, a maska pola hasła
@@ -120,6 +121,17 @@ class ResultModel extends BaseDatabaseModel
             }
         }
 
+        if (trim($apiKey) === '') {
+            $databaseKey = is_array($storedParams) ? trim((string) ($storedParams['ai_api_key'] ?? '')) : '';
+            $databaseKeyLength = preg_match('/^\*+$/', $databaseKey) ? 0 : mb_strlen($databaseKey);
+            throw new \RuntimeException(
+                'AI_KEY_EMPTY|provider=' . ($provider !== '' ? $provider : '(pusty)')
+                . '|component_chars=' . $componentKeyLength
+                . '|database_chars=' . $databaseKeyLength
+                . '|database_params=' . (is_array($storedParams) ? 'json' : 'unreadable')
+            );
+        }
+
         $feedback = (new AiService())->evaluate(
             $provider,
             $apiKey,
diff --git a/com_testquestions.xml b/com_testquestions.xml
index 1a56bee..989ad96 100644
--- a/com_testquestions.xml
+++ b/com_testquestions.xml
@@ -4,7 +4,7 @@
     <creationDate>2026-10-14</creationDate>
     <author>Komponent</author>
     <license>GNU General Public License version 2 or later</license>
-    <version>1.42.6</version>
+    <version>1.42.7</version>
     <description>COM_TESTQUESTIONS_DESCRIPTION</description>
     <element>com_testquestions</element>
     <namespace path="src">Komponent\Component\Testquestions</namespace>