I was able to modify the Epson Perfection 2400 Photo
driver to work with my 1640SU under Windows 7 x64.
Here's the driver: Epson America, Inc. - Downloading File Page
Open it with 7-Zip (or whatever you use), extract the file named _winzip_
, extract the files contained in _winzip_
using 7-Zip (or whatever you use).
and replace all instances of USB\VID_04B8&PID_011B
and save and close the file.
Now go to the Device Manager, right click your scanner, Update Driver and Software...
Browse my computer..... and use the folder you extracted _winzip_
(with the now modified Es27.inf
That should do it, worked great for me.