reset your wireless router and disable then re-enable your wireless adapter.
usually works for me if my connection is being 'reset' constantly.
A good suggestion if he hasn't tried it already and the problem's only been occuring for a few minutes - however the nature of the question leads me to believe this is a recurring problem not just an intermittent one!
As for pinging it from the command prompt, go to start => run, type in cmd, hit enter, then type
on the command line and see if you get a result. As well as checking if you get any responses, can you also check whether it displays an IP address for google.com? It's possible it's a DNS issue if it doesn't.