Ok so you have a cable modem...that helps. There is a fat telephone cable, called
ethernet, that comes out of your cable modem; is that plugged directly into your computer or is it plugged into something else? If plugged into something else then then plug it into the computer instead, unplug the power from the cable modem, shutdown the computer, plug the power back in the cable modem, wait 5 minutes and then power up the computer again. If plugged directly into the computer then call the ISP (cable provider) and tell them to ping your modem first and then your computer's IP and see if they see a problem with the modem. 99% of the time the modem will ping fine which will indicate a problem with your computer...when I used to do cable modem support I could tell if it was the modem or a user's computer within 30 seconds of answering the call. If the problem is with your computer then you really should consider reinstalling Windows.
Without knowing more about your problem the only thing I can suggest is to back up your files and reinstall Windows. I know it can be difficult and frustrating to try to explain these problems and if you try to phone someone to help you then you might as well buy a new computer for how much it will cost...even if they manage to fix a problem you might still have other problems. Find all your critical data files such as Excel spreadsheets (search your hard drive for *.xls) and Word documents (search for *.doc) and burn them to CD. There may be other files you want - I'm just giving you an example. Then find a college kid studying computers or kid in the neighborhood that knows about computers and pay him/her $50 to reinstall Windows for you. I see ads on Craigslist (
www.craigslist.org) asking for this kind of help all the time...not sure where you live but maybe you could find someone in your community to give you a hand. Good luck - watch and listen those that help you and maybe you can take the power back...computers only do what you tell them to do.
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