Sending PGP-encrypted messages between any email service Proton Mail allows you to include the public key needed to decrypt any PGP-encrypted messages you send. However, to use PGP, the sender and ...

PGP is an example of a public-key encryption system. Each person using PGP has a private key, which they keep secret, and a public key, which they publish.

, but each recipient of the message would have to be given the key to decrypt it. This symmetric, or private key encryption, requires that both parties have the same key.

PGP has shipped an update to its enterprise message encryption software that adds support for Lotus Notes and integrates Symantec's antivirus technology.