diff --git a/htdocs/core/class/commonobject.class.php b/htdocs/core/class/commonobject.class.php
index 1f64741385f..f429225640b 100644
--- a/htdocs/core/class/commonobject.class.php
+++ b/htdocs/core/class/commonobject.class.php
@@ -6148,7 +6148,7 @@ abstract class CommonObject
 								//var_dump($this->oldcopy);exit;
 								if (is_object($this->oldcopy)) {		// If this->oldcopy is not defined, we can't know if we change attribute or not, so we must keep value
 									//var_dump($this->oldcopy->array_options[$key]); var_dump($this->array_options[$key]);
-									if ($this->array_options[$key] == $this->oldcopy->array_options[$key]) {	// If old value crypted in database is same than submited new value, it means we don't change it, so we don't update.
+									if (isset($this->oldcopy->array_options[$key]) && $this->array_options[$key] == $this->oldcopy->array_options[$key]) {	// If old value crypted in database is same than submited new value, it means we don't change it, so we don't update.
 										$new_array_options[$key] = $this->array_options[$key]; // Value is kept
 									} else {
 										// var_dump($algo);