Something I did without thinking. Anyway, since I never
turn off the router or modem, I forgot what to do ( and felt stupid when the tech pointed it out). First, plug the computer straight into the modem. Then goto Start-Run-Command-and try IPCONFIG( if you don't remember the numerical IP address). Close firewall and virus protection first(hate that part), then open a browser and logon using that number. Troubleshoot from there. If this gets you back to where you need to be, plug everything back in and reconfigure your router.
If not, then check ethernet card, settings, etc. If the Ecard is dead, think about replacing with a Gigabit card for about the same price(in most places). Go forward, it will be of use later. chuck