In order to use the PIVKey command line tool and the Microsoft utility "certutil", you will need to open up a command window. To do so in Windows 10 you can use the Windows Start menu. Click the Start button in the lower left hand corner of your screen to open the Start Menu.
Type "cmd" in the empty search box and click Command Prompt in the results.
(To open an elevated command prompt, for tasks such as loading or deleting certificates, Right-Click the Command Prompt as shown below and select "Run as Administrator".)
This will open a window that looks like this:
You can use the Microsoft utility "certutil" from any directory but to use the PIVKey command line tool, you need to navigate to the directory where the PIVKey Admin Tools were installed. The default is C:\Program Files (x86)\PIVKey Installer\PIVKey Admin Tools. To get there, type:
cd C:\Program Files (x86)\PIVKey Installer\PIVKey Admin Tools and press Enter.
You are now ready to use the PIVKey Tool!