I use Symantec Encryption Desktop v.10.3.0 and Microsoft Outlook v. 14.0.6129.5000 (32bit) in my pc.
I use SEC to encrypt a zip file containing a text document and then I attach the encrypted archive (filename.zip.pgp) and send it through Microsoft Exchange Server.
If I do this procedure manually the receiver gets a *.pgp attachment containing a zip, that contains a *.txt file.
If a use python's smtplib and email modules for sending the e-mail and gnupg module for the encryption I have the following problem:
If the receiver saves the .pgp archive in her disk and then uses SEC, the file opens fine.
But if the receiver double-clicks in the attachment inside Outlook the pgp file opens showing a *.txt file (and not a zip file) with the following filename:  "filename zip.txt"
This is of course the zip file but with a different extension (txt).
Anyone knows why is this happening?
As far as I recall, when Symantec Encryption Desktop creates a PGP file, it is also zipping. This is how I used the Symantec Command Line API tool, as I would select multiple files for encryption and they would end up in a single file (like a zip).
So, you would probably remove any Outlook quirks by just PGPing the txt file, without the zip step in the middle.
If I open pgp attachments in Outlook the file extension changes