OpenPGP (GnuPGP) is a free replacement for the Pretty Good Privacy (PGP) program developed by Philip Zimmermann in the early 1990s. Because it does not utilize the IDEA algorithm. GnuPG is a RFC2440 (OpenPGP) compliant application. Keep in mind that encryption protects the contents against an unwanted party reading it. Digital signatures make sure that it was not modified and comes from a specific sender.
Gpg4win supports both relevant cryptography standards, OpenPGP and S/MIME (X.509), and is the official GnuPG distribution for Windows. It is maintained by the developers of GnuPG.
Gpg4win runs on Windows XP, Vista, Windows 7, and Windows 10. Both 32 and 64bit systems are supported.
The Outlook plugin GpgOL is compatible with Microsoft Outlook 2003 and 2007.
Important: Currently, the Windows Explorer plugin GgpEX works with 32bit Explorer only. It is possible to use the 32bit Explorer on some 64bit Windows. A 64bit update is in progress. All file crypto features of GpgEX on Windows 64bit can be accessed from the file menu of Kleopatra (e.g. File > Sign/encrypt file).
SHA-256 Checksum: 477f56212ee60cc74e0c5e5cc526cec52a069abff485c89c2d57d1b4b6a54971
GPG Suite formally known as PGP Tools is developed and supported by the open source community.
GPGTools (12. February 2018) runs on macOS 10.9 and newer.
SHA-256 Checksum: f2be13ca1aeb7d29ba46134d1d38f88de9c52eb1270ac00fd5f1bc305fd5921e