There's no dedicated fax line here. The prehistoric faxmodem is connected to the POTS line. The software is prehistoric WinFax (these days it's owned by Symantec, but I don't think it was, back then). It all works flawlessly, as it has done for many years. It costs 0p a month, and a few pence when I send a fax.
Windows 7 comes with a bit of kit called "Windows Fax and Scan" which is supposed to be able to scan a document and then fax it. It doesn't work. It alone, of all the software connected to the PC, can't see the scanner. It insists, firmly and irrevocably, that there isn't one.
So I scan the document with Paint Shop Pro 5 (far quicker than the latest, very clever but very bloated Paint Shop Pro 12), save the JPEG, and then use WinFax to open and fax the JPEG.
About once or twice a year I need to do that. I'm happy with the process, but disappointed that Microsoft couldn't get Fax and Scan to work. I have "raised a ticket" but they seem uninterested. Status quo ante.