I have an Epson WiFi multifuncional, and was very happy to see that I needed no additional software at all to make it work. OS X had everything built in. For scanning, I use Image Capture. It’s fairly basic, but it does the job of scanning a batch of duplex pages in to a single PDF.
Sometimes, however, Image Capture hangs on “Waiting for scanner…”. Restarting Image Capture doesn’t help; restarting the multifunctional neither, nor did turning the Mac’s WiFi off and on again. Restarting OS X entirely did solve the issue, but I don’t call that a solution.
Today, I came across a post of Packetrider on an HP forum. He figured out that killing the Image Capture Extension
process solves the problem as well:
killall "Image Capture Extension"