Getting to end-September and still waiting for Microsoft and/or Epson to do something about this infuriating problem.
Epson's response today was: "Okay, I am having a feeling something to do with the windows update has knocked some things around a little. We have in the past advised to contact windows to see if they can see what is stopping the product from operating correctly as the drivers and patch should resolve the issue."
Using Photoshop Elements or Foxit doesn't seem to work, not with V100 scanner.
Nor does Administrator mode. Nor does Windows 8 compatibility mode.
Nor does reinstalling the drivers.
Just one positive thing though: scanner and Epson software do usually work OK in B/W mode, though never in grayscale or color.
It's so annoying.
You have an XP-era scanner and have tried the available fixes. The latest driver was released five years before Windows 10. With the Windows semi-annual feature updates, it was just a matter of time before one of them was no longer compatible with the old driver. This is not a Microsoft problem--it's the responsibility of hardware manufacturers to maintain compatibility. You might want to look into VueScan, which is not free, but it has resurrected many scanners that were abandonded by their manufacturers.