diff --git a/includes/discovery/os/hp.inc.php b/includes/discovery/os/hp.inc.php
index 22fbb1b7b..2683d0a45 100644
--- a/includes/discovery/os/hp.inc.php
+++ b/includes/discovery/os/hp.inc.php
@@ -2,7 +2,7 @@
 
 if (!$os)
 {
-  if(preg_match('/HP [a-zA-Z0-9-]+ Switch Software Version/',$string)) { $os = "hp"; }
+  if(preg_match('/HP [a-zA-Z0-9-]+ Switch Software Version/',$sysDescr)) { $os = "hp"; }
 }
 
 ?>