Problem with Network Adapters for Wifi?

I bought a new Gateway laptop from Best Buy about 3 weeks ago. My roommate used to use this unsecured wifi connection on her laptop which I started using too..I brought the laptop in to work to setup vpn a few days after I bought it. Since the, everytime I try and connect to the unsecured free Wifi, it gives the message "Diagnose Conenction problems". When I click on it, it displays "Problem with Network Adpaters". I dotn even have the windows cd that the laptop came with to put all the default setting backs. I did a system restore yesterday and still the same problem. Now, I have a new laptop but I cannot even use it. I am planning to buy wifi connection of my own but am scared that it is going to have the saem network adapters issue!!! Pls help and advice if possible. Thnx in advance