Using GPG on Windows is possible at the command line, or with a GUI front end. Here are guides:
- GPG4Win is a free software suite and includes an implementation of Gnu Privacy Guard for Windows.
- Using GPG on Windows at the command line is also possible, though more complicated than doing so on Mac/Linux systems. A Practical Introduction to GNU Privacy Guard in Windows is one description of doing so, written in 2005.
- Installing and configuring PGP in Windows, (Windows 7).
- GPG command-line on Windows, some tips from a tech forum, including VBscripting.