Install Windows fax driver
See also Faxing Your Plan
If your Windows installation has not installed the fax driver, Here's how to pull it out of its hiding place.
Windows begins to install the Fax program. If requested, insert your Microsoft Windows XP CD and click OK.
(No Microsoft Windows CD? Before assuming you're completely out of luck, tell Windows to look in this folder, instead: C:\windows\i386\, as some manufacturers hide it in there.)
Click Finish when installation is through.