I got a laptop from my parents for Xmas
When I tried to connect it it the internet it kept asking me for the security key/passphrase which I had no idea where to find
I went onto the web site for the router (I have a Belkin one) + was able to reset my security key - although it took a few tries to get it to reset
I got the instructions by typing 'how do i rest the security key for my belkin router' into google
Try this - hope it works for you