I pull up the Command Prompt; it's another black box with white text that kinda looks like MSDOS and I type "fciv.exe." Nothing happens; it says "fciv.exe is not recognized as an internal or external command, operable program or batch file."
You have to navigate to the correct folder/directory first. Your prompt probably appears as C:\Users\username>. You will to use the 'cd' command.
Typing "cd" doesn't do anything either; I type "cd", hit enter and the same C:\Users\username> appears right below it.
If fciv is in C:\Windows, you can run it from anywhere. In that case,
fciv [____.exe] -sha1 --> Will run fciv on the file in question (____.exe = full file path)
If not,
cmd /K "cd /d c:\WINDOWS\" --> Will create a cmd window at the C:\Windows directory (replace c:\windows with the folder housing gpg4win-2.2.1)
fciv gpg4win-2.2.1.exe -sha1