diff --git a/htdocs/admin/mails.php b/htdocs/admin/mails.php
index 7c72825ad60..52f82b27630 100644
--- a/htdocs/admin/mails.php
+++ b/htdocs/admin/mails.php
@@ -88,13 +88,17 @@ if ($action == 'update' && !$cancel) {
 		dolibarr_set_const($db, "MAIN_MAIL_SMTP_PORT", GETPOST("MAIN_MAIL_SMTP_PORT", 'int'), 'chaine', 0, '', $conf->entity);
 		dolibarr_set_const($db, "MAIN_MAIL_SMTP_SERVER", GETPOST("MAIN_MAIL_SMTP_SERVER", 'alphanohtml'), 'chaine', 0, '', $conf->entity);
 		dolibarr_set_const($db, "MAIN_MAIL_SMTPS_ID", GETPOST("MAIN_MAIL_SMTPS_ID", 'alphanohtml'), 'chaine', 0, '', $conf->entity);
-		dolibarr_set_const($db, "MAIN_MAIL_SMTPS_PW", GETPOST("MAIN_MAIL_SMTPS_PW", 'none'), 'chaine', 0, '', $conf->entity);
+		if (GETPOSTISSET("MAIN_MAIL_SMTPS_PW")) {
+			dolibarr_set_const($db, "MAIN_MAIL_SMTPS_PW", GETPOST("MAIN_MAIL_SMTPS_PW", 'none'), 'chaine', 0, '', $conf->entity);
+		}
 		if (GETPOSTISSET("MAIN_MAIL_SMTPS_USE_OAUTH")) {
 			dolibarr_set_const($db, "MAIN_MAIL_SMTPS_USE_OAUTH", GETPOST("MAIN_MAIL_SMTPS_USE_OAUTH", 'none'), 'chaine', 0, '', $conf->entity);
 			$method = GETPOST("MAIN_MAIL_SMTPS_USE_OAUTH", 'aZ09') == 1 ? 'XOAUTH2' : 'LOGIN';
 			dolibarr_set_const($db, "MAIL_SMTP_AUTH_TYPE", $method, 'chaine', 0, '', $conf->entity);
 		}
-		dolibarr_set_const($db, "MAIN_MAIL_SMTPS_OAUTH_SERVICE", GETPOST("MAIN_MAIL_SMTPS_OAUTH_SERVICE", 'none'), 'chaine', 0, '', $conf->entity);
+		if (GETPOSTISSET("MAIN_MAIL_SMTPS_OAUTH_SERVICE")) {
+			dolibarr_set_const($db, "MAIN_MAIL_SMTPS_OAUTH_SERVICE", GETPOST("MAIN_MAIL_SMTPS_OAUTH_SERVICE", 'none'), 'chaine', 0, '', $conf->entity);
+		}
 		dolibarr_set_const($db, "MAIN_MAIL_EMAIL_TLS", GETPOST("MAIN_MAIL_EMAIL_TLS", 'int'), 'chaine', 0, '', $conf->entity);
 		dolibarr_set_const($db, "MAIN_MAIL_EMAIL_STARTTLS", GETPOST("MAIN_MAIL_EMAIL_STARTTLS", 'int'), 'chaine', 0, '', $conf->entity);
 		dolibarr_set_const($db, "MAIN_MAIL_EMAIL_SMTP_ALLOW_SELF_SIGNED", GETPOST("MAIN_MAIL_EMAIL_SMTP_ALLOW_SELF_SIGNED", 'int'), 'chaine', 0, '', $conf->entity);