Kleopatra is an open source encryption and digital signing application for Windows, Linux and Mac OS X. It is designed to be an easy-to-use interface to OpenPGP and X.509, as well as many other encryption and digital signing technologies. The app provides support for both symmetric and public key cryptography, as well as secure store and backup of private keys, encryption of files and emails, and digital signing of documents. It also integrates with popular email clients such as Mozilla Thunderbird and Microsoft Outlook.
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