diff --git a/htdocs/core/class/conf.class.php b/htdocs/core/class/conf.class.php
index b3991ecfcf2..d70de618be8 100644
--- a/htdocs/core/class/conf.class.php
+++ b/htdocs/core/class/conf.class.php
@@ -967,6 +967,10 @@ class Conf
 				$this->global->MAIN_MAIL_ADD_INLINE_IMAGES_IF_DATA = 1;
 			}
 
+			if (!isset($this->global->MAIL_SMTP_USE_FROM_FOR_HELO)) {
+				$this->global->MAIL_SMTP_USE_FROM_FOR_HELO = 2;
+			}
+
 			if (!defined('MAIN_ANTIVIRUS_BYPASS_COMMAND_AND_PARAM')) {
 				if (defined('MAIN_ANTIVIRUS_COMMAND')) {
 					$this->global->MAIN_ANTIVIRUS_COMMAND = constant('MAIN_ANTIVIRUS_COMMAND');
diff --git a/htdocs/core/class/smtps.class.php b/htdocs/core/class/smtps.class.php
index e7b0207595a..fe1f90dd735 100644
--- a/htdocs/core/class/smtps.class.php
+++ b/htdocs/core/class/smtps.class.php
@@ -665,13 +665,17 @@ class SMTPs
 					if (!is_numeric($conf->global->MAIL_SMTP_USE_FROM_FOR_HELO)) {
 						// If value of MAIL_SMTP_USE_FROM_FOR_HELO is a string, we use it as domain name
 						$hosth = $conf->global->MAIL_SMTP_USE_FROM_FOR_HELO;
-					} else {
+					} elseif ($conf->global->MAIL_SMTP_USE_FROM_FOR_HELO == 1) {
 						// If value of MAIL_SMTP_USE_FROM_FOR_HELO is 1, we use the domain in the from.
-						// If the from to is 'aaa <bbb@ccc.com>', we will keep 'ccc.com'
+						// So if the from to is 'aaa <bbb@ccc.com>', we will keep 'ccc.com'
 						$hosth = $this->getFrom('addr');
 						$hosth = preg_replace('/^.*</', '', $hosth);
 						$hosth = preg_replace('/>.*$/', '', $hosth);
 						$hosth = preg_replace('/.*@/', '', $hosth);
+					} elseif ($conf->global->MAIL_SMTP_USE_FROM_FOR_HELO == 2) {
+						// If value of MAIL_SMTP_USE_FROM_FOR_HELO is 2, we use the domain in the $dolibarr_main_url_root.
+						global $dolibarr_main_url_root;
+						$hosth = getDomainFromURL($dolibarr_main_url_root, 1);
 					}
 				}