diff --git a/attached_assets/image_1754941674961.png b/attached_assets/image_1754941674961.png
new file mode 100644
index 0000000..e9523ad
Binary files /dev/null and b/attached_assets/image_1754941674961.png differ
diff --git a/server/storage.ts b/server/storage.ts
index afeccaa..96f244a 100644
--- a/server/storage.ts
+++ b/server/storage.ts
@@ -694,15 +694,23 @@ export class DatabaseStorage implements IStorage {
       const [newUserGroup] = await db.insert(userGroups).values(userGroup).returning();
       return newUserGroup;
     } catch (error: any) {
-      // If created_at column doesn't exist (production), insert without it
+      // If created_at column doesn't exist (production), use raw SQL
       if (error?.code === '42703' && error?.message?.includes('created_at')) {
-        console.log('⚠️ Production mode: user_groups table missing created_at column, inserting without it');
-        const userGroupWithoutCreatedAt = {
+        console.log('⚠️ Production mode: user_groups table missing created_at column, using raw SQL');
+        
+        // Use raw SQL to insert without created_at column
+        await db.execute(sql`
+          INSERT INTO user_groups (user_id, group_id) 
+          VALUES (${userGroup.userId}, ${userGroup.groupId})
+          ON CONFLICT DO NOTHING
+        `);
+        
+        // Return a UserGroup object with null created_at
+        return {
           userId: userGroup.userId,
-          groupId: userGroup.groupId
+          groupId: userGroup.groupId,
+          createdAt: null
         };
-        const [newUserGroup] = await db.insert(userGroups).values(userGroupWithoutCreatedAt).returning();
-        return { ...newUserGroup, createdAt: null };
       }
       throw error;
     }
diff --git a/test-user-groups.js b/test-user-groups.js
new file mode 100644
index 0000000..228816c
--- /dev/null
+++ b/test-user-groups.js
@@ -0,0 +1,36 @@
+// Test script pour vérifier l'attribution des groupes en production
+// À exécuter avec: node test-user-groups.js
+
+import { storage } from './server/storage.js';
+
+async function testUserGroups() {
+  try {
+    console.log('🧪 Test d\'attribution des groupes...');
+    
+    // Test data
+    const testUserGroup = {
+      userId: 'test_user_123',
+      groupId: 1
+    };
+    
+    console.log('📝 Tentative d\'attribution du groupe:', testUserGroup);
+    
+    const result = await storage.assignUserToGroup(testUserGroup);
+    
+    console.log('✅ Attribution réussie:', result);
+    console.log('🎉 Le problème d\'attribution des groupes est résolu !');
+    
+  } catch (error) {
+    console.error('❌ Erreur lors du test:', error);
+    console.error('Code d\'erreur:', error?.code);
+    console.error('Message:', error?.message);
+  }
+}
+
+if (process.env.NODE_ENV === 'production') {
+  console.log('🏭 Exécution en mode production');
+  testUserGroups();
+} else {
+  console.log('🛠️ Ce test est conçu pour la production');
+  console.log('Pour tester localement, définissez NODE_ENV=production');
+}
\ No newline at end of file