Email Encryption for Windows
Is the source code available for SecExMail ?
The source code for the core cryptographic components of SecExMail is freely available on the internet.
Twofish block cipher
At the time of writing the Twofish homepage can be found at http://www.counterpane.com/twofish.html.
ISAAC
At the time of writing, the ISAAC home page can be found at http://burtleburtle.net/bob/rand/isaacafa.html.
OpenSSL
SecExMail contains cryptographic software from the OpenSSL project at www.openssl.org