Confidant Mail is an open-source non-SMTP cryptographic email system optimized for large file attachments. It is a secure and spam-resistant alternative to regular email and online file drop services. It uses GNU Privacy Guard (GPG) for content encryption and authentication, and TLS 1.2 with ephemeral keys for transport encryption.
Confidant Mail is the easiest way to use PGP encryption. You can download and install the software and start using it in a few minutes. The only information you have to know and type in is your name, email address, and a password. No complex setup is required. Your public key will be created automatically.
Confidant Mail version 0.35 includes GPG 1.4.21, which has an important security fix CVE-2016-6313. You should upgrade older versions.
New tutorial May 2016: Click Windows or Linux for a step-by-step screen recording showing you how to install and use Confidant Mail.
New feature April 2016: Click here to get alerts by text or regular email when new CM arrives.
Cick here to read why Confidant Mail is better than encrypted webmail.
All messages are encrypted and signed with GNU Privacy Guard.
The server administrator cannot read or alter your email.
Public keys are retrieved automatically using DNS or Kademlia peer-to-peer.
Passive snoopers cannot see who is communicating with whom.
Forward secrecy of messages via encryption subkey rotation
Two or more machines can access an account with automatic folder sync
Attachment length is unlimited. Sending multi-gigabyte files is easy.
Large messages are transferred in hash-checked blocks, like BitTorrent.
Positive acknowledgment of all messages confirms delivery.
Proof-of-work makes junk mail costly for the sender.
Messages can be forwarded with the cryptographic signature intact.
Sign up for a free server account, run your own server easily, or use peer-to-peer mode.
Change servers without changing your email address.
Servers are paired and replicated for high availability.
Optional TOR or I2P anonymity.
Use your existing email address. The recipient must have Confidant Mail.
Works on Windows XP/7/8, MacOS, and Linux.
Client automatic configuration makes setup easy.
Support for OpenPGP smartcard
Version 0.35 is available, with GPG 1.4.21 which fixes an important security bug
Version 0.34 fixed Unicode search bug, IPv6 support
Added printing and fixed a foreign character bug (0.33)
Added full text search, find button, and outbound bandwidth throttling (0.32)
Added proof-of-work bypass tokens and save list column widths (0.31)
Added global font size adjustment, save default font selection, fix Mac/Linux spellcheck (0.30)