Connected but without network
Since a few days ago, i realized that my network was not working. At first i thought was a problem with the provider, but after a few tests it pointed to a problem with my airport express. That's what happens: i'm using the internet, then suddenly the network doesnt work(in all my devices, cell, notebook,ipad) but i'm still connected. So I unplug the power cord on the airport and then plug back in and it starts working again, but then later (20 minutes) it happens again and the only way the sort is to unplug and plug back in. I wonder whats wrong?