diff --git a/setup.php b/setup.php
index 886d523f..9f392a84 100644
--- a/setup.php
+++ b/setup.php
@@ -847,7 +847,7 @@ if(isset($_POST['add_user'])){
   $password = password_hash($_POST['password'], PASSWORD_DEFAULT);
 
   //Generate master encryption key
-  $site_encryption_master_key = keygen();
+  $site_encryption_master_key = bin2hex(random_bytes(8));
 
   //Generate user specific key
   $user_specific_encryption_ciphertext = setupFirstUserSpecificKey($_POST['password'], $site_encryption_master_key);