Laptop won't recognize home router with Xubuntu
I have a Lenovo T400 laptop and have been using Xubuntu very successfully, both at home and wherever wifi is available. I came home this evening and my laptop won't connect with my home router. It asks for my authentication code (which I provide) but the "enter" switch will not activate. I can't imagine what has gone wrong; I've changed nothing. Any suggestions? This is very frustrating! Thank you.