AxCrypt : Simply right click on the file and encrypt the file and for decrypting the files just double click on that file. AxCrypt also supports self decrypting files so these types of files can be sent over the network or to email recipients. AxCrypt available only for windows platform
WinPT: Windows Privacy Tools (WinPT) is a collection of multilingual applications for easy digital encryption and signing of content. It’s GnuPG-based, compatible with OpenPGP compliant software (like PGP) and free for commercial and personal use under the GPL.
PeaZip: PeaZip open, create and encrypt zip files and other compression file formats. PeaZip also split/join files (file span), wipe files (secure deletion), compare, checksum and hash files, system benchmark, and more.
MCrypt: MCrypt is a replacement for the old crypt() package and crypt(1) command, with extensions. It allows developers to use a wide range of encryption functions, without making drastic changes to their code. It allows users to encrypt files or data streams without having to be cryptographers. Above all, it allows you to have some really neat code on your machine.
Hide In Picture: Hide In Picture is a program that allows you to conceal files inside bitmap pictures, using a password. The pictures look like normal images, so people will not suspect there is hidden data in them.
Steghide : Steghide is a steganography program that is able to hide data in various kinds of image- and audio-files. The color- respectivly sample-frequencies are not changed thus making the embedding resistant against first-order statistical tests.
GPGrelay: This e-mail relaying server signs or encrypts e-mail communications using GnuPG (Gnu Privacy Guard) and your existing e-mail client. The developers are careful to note that this app only protects e-mail in transit—it is still stored in its decrypted state on your computer.
MailCrypt: MailCrypt can used to encrypt, decrypt, and sign messages and usenet articles using either PGP or GnuPG. One warning: MailCrypt may not be secure when used on an NT workstation (site has details).
Open Signature :This digital signature project supports all Open SC cards and aims to be the first single app that can be used with cards from multiple countries. Open Signature originally focused on cards used in Italy but has branched out.
Crypt : Ultra-fast and lightweight, Crypt can be used encrypt or decrypt just about anything on your Windows system, including regular files and directories, consoles, communication resources, disk devices, and more. Operating System: Windows.
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Source : Internet