Detecting non-existent modem

Windows XP keeps detecting an Aztech CNR v.92 modem and installing it. I
don't have a modem - I have a broadband connection. I do have a Packard Bell
1200 Diamond plus scanner, linked through a USB, and it doesn't work when
the 'modem' is installed, even though Device Manager says the scanner is
working OK. I keep uninstalling in device manager, and in add/remove
programs, but it just detects it again.

If I can't solve the underlying problem, how can I turn off automatic
hardware detection?

Its driving me mad!

Nicola Normandale