GnuPG and PGP are public key encryption programs, they are nice and convenient and helpful at avoiding sending ‘important’ content in the clear in email (SMTP is plain-text you remember, right?) Often console-based email clients can be fussy to setup to use this software. Here’s a quick guide, stolen from someone else (Stolen-content).

Basically the PINE solution is to use inbound message filters (display-filters) when the message is displayed to the user and sending-filters when being sent out the door. The quick and dirty, incase the linked-to page above disappears is:

  1. set the display-filters in ‘config’ to:
       _BEGINNING("-----BEGIN GnuPG MESS")_ /usr/bin/gpg -d
       _BEGINNING("-----BEGIN PGP MESS")_ /usr/bin/gpg -d 
    
  2. set the send-filters in ‘config’ to:
     /home/userid/.gnupg/gpgclearsign --clearsign
     /home/userid/.gnupg/gpgencrypt -eas -r _RECIPIENTS_ 
    

    (be sure that your gnupg directory has these commands as symlinks to the gpg command)
  3. look for ‘send filters’ when you Ctrl-X to send the email…

Simple enough, eh?