Add a certificate or PGP key from an attachment
If you are enrolled with the PGP Universal Server, you can't add PGP keys from attachments.
In a message, click the certificate or PGP key attachment at the end of the message.
Click Retrieve Certificate or Retrieve PGP Key.
Click the certificate or PGP key.
• To import the certificate or PGPkey, click Import Certificate or Import PGP Key.
• To import and trust the certificate or PGP key, click Trust Certificate or Trust PGP Key
I can't open an attachment in an encrypted message,