How to set up security on my wireless links system

[Bob_30]

I have a links wireless system, I am trying to make this a secure connection. I have gon into the property settings and everytime I try to set the security to wpa2 or even wpa it I lose my internet connectivety. I can't get the security key needed.

Thanks for any help
Bob

 

[Emerald]

are you connected to the router via network cable while you are configuring it?