Trisquel crash if not connected with ethernet connection.. help!

Hi, i'm a new user and i'm not very expert about linux, but i have i little problem. I have an Asus aspire one 522 and i can use it only when it is connected by ethernet cable: in fact if internet connetion crashes or if i unplug the internet cable the netbook crash (everything on the desktop stops) and i have to restart it... if somebody can help me... :)