Let's assume he is connected, otherwise the above in checking what connection, if at all IE will use becomes a factor.
If connected and getting this, then try an IP address in the browser. If you get a site up that way, but not thru it's domain name, then you likely have a DNS resolution issue with the service you are on, or your DNS settings are not correct, (you may be specifying a set, where in most cases the selection of "assigned by server" will suffice.)
Anytime you are connected and not getting pages, I advise to try the IP checking, can save time in issue determination ...
and the latter of the above is also true, it could be the browser being corrupt. But we need to hear more info on the conditions at the time (connected, not connected, etc.)