Well... If you're to be helped, it'd be important for those trying to help you to know a bit more about the computer itself... What you say right now amounts to barely more than "it's not working right."

But seriously, what is the type of connection your computer has to the network? If you mean that you use Ethernet to connect it to the network (and hence modem) what brand is the network adapter, or if it's built into the motherboard, what is the brand and model of that motherboard?
Likewise, what about your Internet connection itself? What is your provider, etc.?