Для отправки использую плагин
Custom certificate
https://moodle.org/plugins/mod_customcert/versionsВ отправленном письме не прикрепляется файл сертификата и выдает вот такие сообщения:
MIME-Version: 1.0
Content-Type: multipart/mixed;
boundary="b1_gftVsR5JS9yCQWQ6G9U76bvYWJzQecxvBsuCtjvY84"
Content-Transfer-Encoding: 8bit
This is a multi-part message in MIME format.
--b1_gftVsR5JS9yCQWQ6G9U76bvYWJzQecxvBsuCtjvY84
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
--b1_gftVsR5JS9yCQWQ6G9U76bvYWJzQecxvBsuCtjvY84
Content-Type: application/pdf; name=123_testtest.pdf
Content-Transfer-Encoding: base64
Content-Disposition: attachment; filename=123_testtest.pdf
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