This TNEF containing email is signed. When viewed in Outlook it warns “…problems with the signature.” And if you click the warning icon it tells you the “digital signature is not valid”. But the email displays just fine.
I then convert this to a standard internet mail, using Aspose. The created .eml file, when opened in Outlook, shows: “An error occurred in the underlying security system. An internal error occurred.”. The conversion was as simple as this:
MailMessage msg = MailMessage.load(in); msg.save(outFile, SaveOptions.getDefaultEml())
So although the signature may not be valid - it would be really great if the converted version was able to display the email in Outlook - as it does with the tnef version.
SMIME-ProblemMailExample.zip (24.1 KB)