diff --git a/checkAuth.php b/checkAuth.php
index 5aa5834..493ef83 100644
--- a/checkAuth.php
+++ b/checkAuth.php
@@ -2,6 +2,14 @@
 session_start();
 header('Content-Type: application/json');
 
+// Check if users.txt is empty or doesn't exist
+$usersFile = __DIR__ . '/users.txt';
+if (!file_exists($usersFile) || trim(file_get_contents($usersFile)) === '') {
+    // Return JSON indicating setup mode
+    echo json_encode(["setup" => true]);
+    exit();
+}
+
 if (!isset($_SESSION['authenticated']) || $_SESSION['authenticated'] !== true) {
     echo json_encode(["authenticated" => false]);
     exit;