Some drivers don't use the add hardware wizard. Some are very odd in that you unzip a file, or run a setup.exe in the .zip file. I've used various Epson drivers and the current models didn't use the add hardware.
I would check the install notes again.
I have an HP Pavillion PC running Windows Me. I have an old Epson Color Stylus 740 printer that I want to run on this computer. I've found the drivers at the Epson and Download.com websites and downloaded it. When I go through the "Install new Hardward Wizard," my driver software isn't found. I've tried placing it in different locations, even copying it to a CD rom and having the wizard find it from there.