1. Does your internet connection run correctly to its modem?
2. Do you have a router, if so does the cable from your modem run to that and connect to the right slot?
3. Do you have the correct cable running from your router to your PC (if you do not have a router, then directly from your modem)?
4. When you turn on your PC if you watch where the plug is inserted, are there any activity lights at all?
Lets make sure you are connected properly before we go tampering with the operating system (like Windows)