It sounds as though the internet might be DSL. If that is the case, it has to be a phone line, as though you were connecting another phone.
Although I had some trouble getting the USB fax modem installed when I ran the drivers supplied with it, Device Manager revealed the modem model number, and that allowed me to search for drivers on the Net, resulting in Device Manager showing the modem and as non-problematical. Using the method outlined at http://www.thewindowsclub.com/set-up-your-windows-7-computer-to-send-and-receive-faxes, I can get only as far as the fax-set-up Window, because the mouse turns into an hour-glass after selecting 'fax modem' and clicking on NEXT; and when I abandon the attempt, an error window tells me : "MS Windows Fax & Scan is not responding". I have no guidance whether to have the modem connected to the phone line during the rest of the setup, and whether the line can be a spur from that going to the broadband modem, or has to have a filtered line, like that which goes to the phones. Can anyone help me make progress with this ?

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