Gpg4win
Gpg4win is an email and file encryption package for most versions of Microsoft Windows and Microsoft Outlook, which utilises the GnuPG framework for symmetric and public-key cryptography, such as data encryption, digital signatures, hash calculations etc. == History of Gpg4win == The original creation of Gpg4win was initiated and funded by Germany's Federal Office for Information Security (BSI) in 2005, resulting in the release of Gpg4win 1.0.0 on 6 April 2006; however Gpg4win and all included tools are free and open source software, and it is typically the non-proprietary option for privacy recommended to Windows users.