Register the YubiKey in YubiOn Portal.
YubiKey must be registered without changing the settings.
You may not be able to use a YubiKey that you have changed your own settings.
Click “YubiKey Management” in the menu on the left side of the screen.
Click the “Add YubiKey” button at the top right of the YubiKey list.
Plug the YubiKey into the USB port and click the YubiKey input field.
Tap on the metal part of the YubiKey.
Input the YubiKey name and click the “Register” button.
Click the “OK” button in the confirmation message.
That’s all for YubiKey registration.