diff --git a/htdocs/margin/admin/margin.php b/htdocs/margin/admin/margin.php
index c041700fa18..4df01332eb1 100644
--- a/htdocs/margin/admin/margin.php
+++ b/htdocs/margin/admin/margin.php
@@ -42,6 +42,7 @@ $action = GETPOST('action', 'aZ09');
  * Action
  */
 
+$reg = array();
 if (preg_match('/set_([a-z0-9_\-]+)/i', $action, $reg)) {
 	$code = $reg[1];
 	if (dolibarr_set_const($db, $code, 1, 'yesno', 0, '', $conf->entity) > 0) {