Mountain Lion restoration.

Hello, i restored my macbook air, but, when i try to start it, i have a white scren with an earth logo spinning on the center. Then i have to connect to a WiFi but my WiFi isn't detected! Probably because i enter a proxy to use my internet. (i'm a student).

Can you propose me a solution? Can i recover my macbook air without internet connection?

(sorry for my bad english, i'm a french student.)