diff --git a/.installed b/.installed
deleted file mode 100644
index e69de29..0000000
diff --git a/install.lock b/install.lock
new file mode 100644
index 0000000..1e7f719
--- /dev/null
+++ b/install.lock
@@ -0,0 +1 @@
+2026-04-01 09:15:21
\ No newline at end of file
diff --git a/install.php b/install.php
index 83a51b9..e9993e2 100644
--- a/install.php
+++ b/install.php
@@ -5,7 +5,7 @@ if (session_status() !== PHP_SESSION_ACTIVE) {
     session_start();
 }
 
-if (file_exists(__DIR__ . '/.installed')) {
+if (file_exists(__DIR__ . '/.installed') || file_exists(__DIR__ . '/install.lock')) {
     die('Installation already completed. To reinstall, delete the .installed file.');
 }
 
@@ -74,6 +74,7 @@ if ($_SERVER['REQUEST_METHOD'] === 'POST') {
         }
     } elseif ($step === 5) {
         file_put_contents(__DIR__ . '/.installed', date('Y-m-d H:i:s'));
+        file_put_contents(__DIR__ . '/install.lock', date('Y-m-d H:i:s'));
         header('Location: login.php');
         exit;
     }
diff --git a/queue_bootstrap.php b/queue_bootstrap.php
index 263a45f..249685a 100644
--- a/queue_bootstrap.php
+++ b/queue_bootstrap.php
@@ -6,7 +6,24 @@ if (session_status() !== PHP_SESSION_ACTIVE) {
 }
 $publicPages = ["login.php", "logout.php", "install.php", "display.php", "ticket.php"];
 $currentPage = basename((string) ($_SERVER["PHP_SELF"] ?? "index.php"));
-if (!file_exists(__DIR__ . "/.installed") && $currentPage !== "install.php") {
+$isInstalled = file_exists(__DIR__ . "/.installed") || file_exists(__DIR__ . "/install.lock");
+if (!$isInstalled) {
+    try {
+        if (file_exists(__DIR__ . '/db/config.php')) {
+            require_once __DIR__ . '/db/config.php';
+            if (function_exists('db')) {
+                $pdo = db();
+                $stmt = @$pdo->query("SELECT COUNT(*) FROM users");
+                if ($stmt !== false && ((int)$stmt->fetchColumn()) > 0) {
+                    $isInstalled = true;
+                    @file_put_contents(__DIR__ . '/install.lock', date('Y-m-d H:i:s'));
+                }
+            }
+        }
+    } catch (\Throwable $e) {}
+}
+
+if (!$isInstalled && $currentPage !== "install.php") {
     header("Location: install.php");
     exit;
 }