diff --git a/htdocs/core/class/CMailFile.class.php b/htdocs/core/class/CMailFile.class.php
index 4dd466d96ab..721e0582824 100644
--- a/htdocs/core/class/CMailFile.class.php
+++ b/htdocs/core/class/CMailFile.class.php
@@ -962,6 +962,8 @@ class CMailFile
 				}
 
 				if ($res) {
+					dol_syslog("CMailFile::sendfile: sendMsg, HOST=".$server.", PORT=".$conf->global->$keyforsmtpport, LOG_DEBUG);
+
 					if (!empty($conf->global->MAIN_MAIL_DEBUG)) {
 						$this->smtps->setDebug(true);
 					}
@@ -1096,7 +1098,11 @@ class CMailFile
 					//$this->logger = new Swift_Plugins_Loggers_EchoLogger();
 					$this->mailer->registerPlugin(new Swift_Plugins_LoggerPlugin($this->logger));
 				}
+
+				dol_syslog("CMailFile::sendfile: mailer->send, HOST=".$server.", PORT=".$conf->global->$keyforsmtpport, LOG_DEBUG);
+
 				// send mail
+				$failedRecipients = array();
 				try {
 					$result = $this->mailer->send($this->message, $failedRecipients);
 				} catch (Exception $e) {