Currently only the
C:\Program Files (x86)\Gpg4win\..\GnuPG\bin
directory is added to the Windows Environment Path variable. But there are also useful binarys (e.g. checksum checking), in the Gpg4win/bin folder. So it would be useful to add
C:\Program Files (x86)\Gpg4win\..\Gpg4win\bin
as well.