if i remember from my poly lessons.
you have to first generate a public key and a private key, and pass
the public key to those you want to have contact with?
then if that person wants to send u an encrypted msg, he will use
your public key to encrypt it, then send to you, and you use your
private key to unlock it.
so if you received encrypted files, you should have the private key
to unlock it. if not, you're not meant to read those files lor.