If you have the documentation for the Liksys router consult it to see how to access the router settings from your computer. WPA security uses a Key and is handy because once a device is "registered" it does not require entry of a Password to reconnect. If someone installed your home Wifi you could contact them to see where they stored the Key. It might be written down on the paper documentation or stored on your computer's Desktop as a file. If you can not find the Key; search the Web for WPA there are several "how to articles" that can help you access your router setup and either locate the current Key or regenerate a new Key. If you regenerate a Key then all the devices that are currently able to access you WiFi will have to reregister with the new Key. Note: the Key is a long string of numbers and letters that must be entered exactly correctly Upper and Lower case included. You will get this worked out, good luck.