Are you using a monitor, keyboard and mouse connected to RPI?
If yes, then you better set up your RPi for SSH from your Windows or Mac Desktop/Laptop.
To do this, you will need to shutdown Pi, disconnect power, slip-out microSD card from Pi and slip it into card reader of your Desktop/Laptop. Then follow the instructions below. If you have already configured WiFi, or are using a wired internet connection to RPi, omit steps for WiFi: