According to an IJM newsletter today, Epson are at it again. Recent firmware updates to a range of their printers have locked out third party carts, and even decoder boards. From what I read, it remains the case that updating just the driver shouldn't cause any problems. The challenge is in knowing that that's all the file you downloaded is going to do, as there are "combo" packages that do both the driver and the firmware, plus sundry other traps for the unwary as well. See the IJM newsletter for details.