unplug your router (have computer off). run your dsl line to one computer. turn it on. type 192.168.0.1 or 192.168.1.0 in your web browser. you should see your yahoo modem connection.
you need to set your main account username and password (check remember your password) and your modem id no. in the modem. I can't walk you through the exact steps from here because I don't have yahoo and I can't see your screen (I fixed a few people's computers with this problem), but yahoo tech support should help
they should have this feature enabled in your name and password by default
The Ultimate Hard Drive Utility PowerMax 4.23. (It now has the ability to clean a Boot Sector virus on the quick erase option.)
The best browser Netscape 8
Have you accidently delete something? Look here (trial. the better one) and here(free)