Snow Leopard sees but can't use Epson Perfection 3490 scanner

After the latest Snow Leopard system security update my EpsonScan software stopped working—it hangs forever. I deleted and re-installed, twice. No change. Other third-party packages such as Prizm and Vuescan hang too. So I learned about and installed Apple's Epson Printer & drivers update. Now the scanner appears in the Print & Fax system preferences pane, but there is no green dot under the icon (as there is for the printer and USB modem) to indicate that it is active. And when I launch Image Capture, either by clicking on its icon or inside of Photoshop (CS6) it says that no scanner is connected to the system.

Has anyone else experienced this problem and discovered a solution?

Many thanks,

Glen