Just today a colleague and I exchanged public gpg keys and I realized that although things were up-to-date on my Linux machines, my Windows laptop was in dire need of a Gpg4win reinstall.
At some point even those of us who are immersed 24×7 in the Unix world have to do stuff on Windows. Since my employer’s e-mail system is on Windows, it’s more efficient for me to use that platform.
Fortunately Gpg4win had a pretty thorough update last October, v2.2.1, while I had something older installed. To do my update I uninstalled the old version and then installed gpg4win-light-2.2.1 to C:\GNU\GnuPG from scratch.
Since I’d not yet created a keyring on the Windows machine, I exported my private key to an ASCII armor file and imported it into a new keyring using GPA (on Windows the default location for the keyring and configuration files is “C:\Users\%USERNAME%\AppData\Roaming\gnupg”).
The Gpg4win Compendium contains some good documentation on the installation, configuration and use of the product.