Encrypting mail storage on mail server

Question

I have been running my own mailserver with postfix and dovecot for some years now.
The mails are stored unencrypted on the server. Is there a possibility to encrypt and decrypt the mails on the server as soon as a user logs in with the password?

Answer 1

You can either use the OS encryption options (e.g. dmcrypt on Linux) or plugins to your server programs, like the scrambler plugin for Dovecot.

The plugin is restricted to a specific software, but in contrast do disk encryption each user has their own encryption key (derived from their password), so not even you can read the mails of your users.

Answer 2

Yes it's possible but it comes with it's own complications. The best example I know is:

Proton Mail