OK. I solved half of the problem. There were actually two issues involved. I needed to install an Epson driver that I thought I had effectively installed before, but it turned out I hadn't. It turned out I had to register the scanner before I could receive the driver. Effective installation of the Epson driver enabled me to use either Image Capture or VueScan effectively on 10.7.4 when the FireWire 800 connection was between my Mac Pro and and the scanner. However, when the Mac Pro is operating 10.7.4 and the iMac that is connected on a local network is operating 10.6.8, the iMac is not able to operate the scanner via scanner sharing. When I connect the FireWire cable from the scanner directly to the iMac, the iMac does operate the scanner, but the Mac Pro using 10.7.4 cannot access the scanner via scanner sharing. When both computers are running 10.6.8, scanner sharing works well regardless of which machine is directly connected to the scanner.

To make that long story short, I initially failed to effectively install the Epson driver for 10.7.4, but succeeded the second time and scanner sharing does not work when one machine is using 10.6.8 and the other is using 10.7.4. Since I've decided to not use iCloud, I'm seriously considering going back to 10.6.8 while waiting for Mountain Lion to appear and then to mature with a few updates.


Mac Pro dual Quad-Core Intel Xeons Early 2008; 16GB RAM; MacOS X 10.11.6, iOS 9.3.5