diff --git a/diagnostic.php b/diagnostic.php
new file mode 100644
index 0000000..b83c819
--- /dev/null
+++ b/diagnostic.php
@@ -0,0 +1,47 @@
+<?php
+require_once __DIR__ . '/db/config.php';
+
+header('Content-Type: text/html; charset=utf-8');
+
+echo "<h1>Diagnostic du Projet Corvara</h1>";
+
+// 1. Test de la connexion
+try {
+    $pdo = db();
+    echo "<p style='color:green;'>✅ Connexion à la base de données réussie.</p>";
+} catch (Exception $e) {
+    echo "<p style='color:red;'>❌ Erreur de connexion : " . htmlspecialchars($e->getMessage()) . "</p>";
+    exit;
+}
+
+// 2. Vérification des tables
+$required_tables = [
+    'users', 'servers', 'channels', 'messages', 'roles', 'server_members', 
+    'channel_members', 'channel_events', 'poll_votes', 'server_badges', 
+    'member_badges', 'custom_emotes', 'voice_sessions'
+];
+
+echo "<h2>Vérification des tables :</h2><ul>";
+foreach ($required_tables as $table) {
+    try {
+        $pdo->query("SELECT 1 FROM `$table` LIMIT 1");
+        echo "<li>$table : <span style='color:green;'>OK</span></li>";
+    } catch (Exception $e) {
+        echo "<li>$table : <span style='color:red;'>MANQUANTE</span> (C'est probablement la cause de l'erreur 500)</li>";
+    }
+}
+echo "</ul>";
+
+// 3. Extensions PHP
+echo "<h2>Extensions PHP :</h2><ul>";
+$exts = ['pdo_mysql', 'mbstring', 'curl', 'gd'];
+foreach ($exts as $ext) {
+    if (extension_loaded($ext)) {
+        echo "<li>$ext : <span style='color:green;'>Installée</span></li>";
+    } else {
+        echo "<li>$ext : <span style='color:red;'>Absente</span></li>";
+    }
+}
+echo "</ul>";
+
+echo "<hr><p>Si des tables sont manquantes, exécutez <b>fix_db.php</b>.</p>";
diff --git a/fix_db.php b/fix_db.php
new file mode 100644
index 0000000..4becb03
--- /dev/null
+++ b/fix_db.php
@@ -0,0 +1,89 @@
+<?php
+require_once __DIR__ . '/db/config.php';
+
+header('Content-Type: text/html; charset=utf-8');
+
+echo "<h1>Réparation de la base de données</h1>";
+
+try {
+    $pdo = db();
+} catch (Exception $e) {
+    die("<p style='color:red;'>Erreur de connexion : " . $e->getMessage() . "</p>");
+}
+
+$tables = [
+    "CREATE TABLE IF NOT EXISTS `channel_events` (
+      `id` int(11) NOT NULL AUTO_INCREMENT,
+      `channel_id` int(11) NOT NULL,
+      `user_id` int(11) NOT NULL,
+      `title` varchar(255) NOT NULL,
+      `description` text DEFAULT NULL,
+      `banner_url` varchar(255) DEFAULT NULL,
+      `banner_color` varchar(20) DEFAULT NULL,
+      `start_date` date NOT NULL,
+      `start_time` time NOT NULL,
+      `end_date` date NOT NULL,
+      `end_time` time NOT NULL,
+      `frequency` varchar(50) DEFAULT NULL,
+      `is_permanent` tinyint(1) DEFAULT 0,
+      `created_at` timestamp NULL DEFAULT current_timestamp(),
+      `enable_reactions` tinyint(1) DEFAULT 0,
+      PRIMARY KEY (`id`)
+    ) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_unicode_ci;",
+
+    "CREATE TABLE IF NOT EXISTS `poll_votes` (
+      `id` int(11) NOT NULL AUTO_INCREMENT,
+      `message_id` int(11) NOT NULL,
+      `user_id` int(11) NOT NULL,
+      `option_index` int(11) NOT NULL,
+      `created_at` timestamp NULL DEFAULT current_timestamp(),
+      PRIMARY KEY (`id`)
+    ) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_unicode_ci;",
+
+    "CREATE TABLE IF NOT EXISTS `server_badges` (
+      `id` int(11) NOT NULL AUTO_INCREMENT,
+      `server_id` int(11) NOT NULL,
+      `name` varchar(255) NOT NULL,
+      `image_url` text NOT NULL,
+      `created_at` timestamp NULL DEFAULT current_timestamp(),
+      PRIMARY KEY (`id`)
+    ) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_unicode_ci;",
+
+    "CREATE TABLE IF NOT EXISTS `member_badges` (
+      `server_id` int(11) NOT NULL,
+      `user_id` int(11) NOT NULL,
+      `badge_id` int(11) NOT NULL,
+      PRIMARY KEY (`server_id`,`user_id`,`badge_id`)
+    ) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_unicode_ci;",
+    
+    "CREATE TABLE IF NOT EXISTS `event_participations` (
+      `id` int(11) NOT NULL AUTO_INCREMENT,
+      `event_id` int(11) NOT NULL,
+      `user_id` int(11) NOT NULL,
+      `created_at` timestamp NULL DEFAULT current_timestamp(),
+      PRIMARY KEY (`id`),
+      UNIQUE KEY `event_id` (`event_id`,`user_id`)
+    ) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_unicode_ci;"
+];
+
+foreach ($tables as $sql) {
+    try {
+        $pdo->exec($sql);
+        echo "<p>✅ Exécution réussie d'une requête de création.</p>";
+    } catch (Exception $e) {
+        echo "<p style='color:orange;'>⚠️ Info : " . $e->getMessage() . " (Peut-être que la table existe déjà)</p>";
+    }
+}
+
+echo "<h2>Vérification finale des colonnes (Correction Erreur 500 courante)</h2>";
+// Ajout de colonnes si manquantes (exemple pour channels)
+try {
+    $pdo->exec("ALTER TABLE `channels` ADD COLUMN IF NOT EXISTS `message_limit` int(11) DEFAULT NULL;");
+    $pdo->exec("ALTER TABLE `channels` ADD COLUMN IF NOT EXISTS `theme_color` varchar(20) DEFAULT NULL;");
+    echo "<p>✅ Mise à jour des colonnes 'channels' terminée.</p>";
+} catch (Exception $e) {
+    echo "<p>ℹ️ Colonnes déjà présentes dans 'channels'.</p>";
+}
+
+echo "<hr><p style='color:green;'>Terminé ! Essayez de rafraîchir votre page index.php.</p>";
+echo "<p style='color:red;'><b>IMPORTANT : Supprimez ce fichier (fix_db.php) après usage.</b></p>";