I am having a simple problem. I am using PGP with thunderbird. These are the instructions I followed: http://www.movements.org/how-to/entry/send-receive-encrypted-email/ I got everything working perfectly. The problem is, when I try to repeat it again on a separate computer, it will not decrypt the email. It keeps saying "Error- secret key needed to decrypt message; click on 'Details' button for more information" How can I solve this problem? I am following all instructions EXACTLY the way I did when I got it working before, but now it won't work on a separate computer.