diff --git a/airtime_mvc/application/controllers/UpgradeController.php b/airtime_mvc/application/controllers/UpgradeController.php
index ae7ad3e7e..2a22999f3 100644
--- a/airtime_mvc/application/controllers/UpgradeController.php
+++ b/airtime_mvc/application/controllers/UpgradeController.php
@@ -123,12 +123,12 @@ class UpgradeController extends Zend_Controller_Action
             ->findOne();
         $airtime_version = $pref->getValStr();
 
-        if ($airtime_version != '2.5.2') {
+        if ($airtime_version != '2.5.2' || $airtime_version != '2.5.1') {
             $this->getResponse()
                 ->setHttpResponseCode(400)
-                ->appendBody("Upgrade to Airtime 2.5.3 FAILED. You must be using Airtime 2.5.2 to upgrade.");
+                ->appendBody("Upgrade to Airtime 2.5.3 FAILED. You must be using Airtime 2.5.1 or 2.5.2 to upgrade.");
             return false;
         }
         return true;
     }
-}
\ No newline at end of file
+}