[Win10prof(64), Outlook-2016(32), Gpg4Win 3.1.10/ GpgOL 2.4.2]
Outlook receives a html mail, signed with valid S/Mime signature.
GpgOL verifies signature => working, green trusted sign, html body content is shown.
**BUT:**
If Outlook-2016 is configured for receiving TXT-only in 'Trust center/Email security' some HTML mails are trunctated, html body is deleted and cannot be recovered, content is lost!
If S/Mime signed mail has been received earlier as html mail without OL conversion and Outlook's configuration has been changed to TXT-only //afterwards//, those mail bodies are deleted/ trunctated too, empty content. Mail headers are still present.
It must be caused by GpgOL's interaction with OL's TXT conversion. If viewing same mail in webmail account by browser //before downloading// it to Outlook/GpgOL, everything is ok.
https://wald.intevation.org/forum/forum.php?thread_id=2120&forum_id=84&group_id=11
**Maybe another related issue is sending S/Mime signed txt only mails:**
Body content is deleted also in OL's 'sended objects'.
If indexing those mails for example with common 'Copernic Desktop search CDS' or 'MailStore', it is indexed twice:
1. as empty mail, no content
2. as .txt file namend 'GpgOL_MIME_structure.txt' with included but not readable S/Mime body.
https://wald.intevation.org/forum/forum.php?thread_id=2117&forum_id=84&group_id=11
Regards, Chris