MIME to MSG conversion ignoring S/MIME format of attached emails

When a MIME email contains another attached email which is S/MIME encrypted and the .eml file is converted to msg, the attached email is marked as IPM.Note after the conversion instead of IPM.Note.SMIME.

Any chance of fixing this bug anytime soon?

@prunerj,

Please provide a sample EML file so that we can reproduce the issue and assist you further.

80a9cb5f-4fe7-4980-9955-ce536de8ad61.zip (6.7 KB)
The attached zip contains .eml file which is the MIME email with S/MIME attached (smime.p7m file was shortened and therefore is damaged, but that is not relevant to the case as we are not decrypting the S/MIME email). The other file is .msg, which is the output from MailMessage conversion.

Best regards,
Jan Pruner

@prunerj,

Please try to use the code snippet given below.

MailMessage msg = MailMessage.Load(EmlSourceFile);
MsgSaveOptions msgSaveOptions = new MsgSaveOptions(MailMessageSaveType.OutlookMessageFormatUnicode);
// Set PreserveSignature to true to preserve the signature.
msgSaveOptions.PreserveSignature = true;
msg.Save(msgFilePath, msgSaveOptions);

We hope that this resolved the issue you were facing. Please feel free to contact us if additional information is required.