Автор: Андрей * 
Здравствуйте.
Да, это EnvelopedCMS + base64
понял, а подписать?
я немного плаваю в этой теме, вопрос может быть сейчас некорректен...
у меня есть исходник
To: 'тут email'
From: 'тут email'
Date: Thu, 13 Aug 2020 15:24:12 +0300
MIME-Version: 1.0
Content-Type: multipart/signed; protocol="application/pkcs7-signature"; micalg=gostr3411-2012-256; boundary="------------ms020001080200040601030700"
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Content-Language: en-US
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--------------ms020001080200040601030700--
когда я пытаюсь подписать тем же сертификатом те же данные, то подписанная часть отличается. я подписываю так oSignedData.SignCades(oSigner,CADESCOM_CADES_BES, true)
