My xp laptop shows a connection with usb broadband but the internet does not connect. The computer connects using LAN or wireless and the USB broadband modem work on another xp computer. I have tried a friends mobile broadband on my laptop but this will not connect to the internet after installation. I have tried winsock, flush DNS, uninstall and reinstall, replacing corrupted and missing files with windows file checker. Apart from formatting and reloading windows, I'm lost. The problem may have occurred after deleting a dns changer virus. I have also tried switching off the firewall, avg and super spyware.