Windows Desktop Cannot Connect to Any Websites

Make sure the data cable is plugged in and reboot.  If that doesn't fix it, there could be a problem with the DNS settings.  The PDF attached to this KB article describes how to fix it.  Login to computer with STAFF credentials.  Student logins don't have permission to change the settings described in the PDF attachment. 

Here is another caveat:  You'll probably only be able to do this on your workstation, not a student computer, because your staff login will only work on computers you have already logged into in the past when the network settings were working.