diff --git a/server/routes.js b/server/routes.js
index a4931ac..9964ea9 100644
--- a/server/routes.js
+++ b/server/routes.js
@@ -1,5 +1,6 @@
 import { readFileSync, writeFileSync, unlinkSync, existsSync, mkdirSync } from 'fs';
-import { join } from 'path';
+import { join, dirname } from 'path';
+import { fileURLToPath } from 'url';
 import { parse } from 'csv-parse/sync';
 import multer from 'multer';
 import crypto from 'crypto';
@@ -7,6 +8,10 @@ import crypto from 'crypto';
 import axios from 'axios';
 import { getSessionStatus, getClientsMap, getSessionIdForSocket } from './broadcast.js';
 
+// __dirname für ES-Module
+const __filename = fileURLToPath(import.meta.url);
+const __dirname = dirname(__filename);
+
 // Bild-Upload-Konfiguration (temporäres Verzeichnis)
 const uploadsDir = join(__dirname, '../tmp');
 if (!existsSync(uploadsDir)) {