re BT Voyager usb adapter 1010?

Hello

A PC had the BT Voyager usb adapter 1010 working on it but then this
PC was disconnected to dela with some viruses on it.

After this, when booted up with the adapter connected, the adapter was
recognised and software automatically installed for it. However cannot
connect to the Internet (via a BT Voyager 1250 router/modem)...

Any ideas on what might be wrong or how to check it out?

One thought - the Sygate firewall is installed on this PC. I have
tried turning this off (or allowing all) but that has been after the
PC has booted up. Could the firewall be stopping the connection whilst
the PC is booting up?

Thanks

Geoff