status of S/MIME and interoperability?

Ed Finnerty edfinnerty at
Tue Feb 2 17:56:27 CET 2016

>> Sending, my impression is that users of Thunderbird and
>> following can receive my encrypted messages, at least without large
>> attachments.  But Outlook users appear not to be able to process
>> encrypted messages from gnus/gpgsm.
> For this particular interop issue, I am curious what is causing the
> difference.  S/MIME encrypted messages are typically in the
> enveloped-data format, which means that the encrypted content is simply
> treated as an attachment.
> If you have access to an MUA interoperable with Outlook, could you
> compare the message structures for the success/failure cases?

I've actually logged the problem here and even attached a script that
easily tests for the issue and can be modified to produce trivial test
output for comparison purposes.

Nobody seemed to really care. So if you do S/MIME with GPG, and use
Thunderbird, every once in a while you'll get an undecryptable message
that you have to save to disk and try to deal with in some way with GPG.

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