diff options
Diffstat (limited to 'Postman/PostmanWpMail.php')
| -rw-r--r-- | Postman/PostmanWpMail.php | 6 |
1 files changed, 4 insertions, 2 deletions
diff --git a/Postman/PostmanWpMail.php b/Postman/PostmanWpMail.php index c108cce..7cd0596 100644 --- a/Postman/PostmanWpMail.php +++ b/Postman/PostmanWpMail.php @@ -65,8 +65,10 @@ if ( ! class_exists( 'PostmanWpMail' ) ) { * @return PostmanMessage */ private function apply_default_headers( $message ) { - $headers[] = 'Message-ID: ' . $this->createMessageId(); - $message->addHeaders($headers); + if(! $message->getMessageId()) { + $headers[] = 'Message-ID: ' . $this->createMessageId(); + $message->addHeaders($headers); + } } /** |