I think the problem may relate to wireless commuication between the Mac and the router or betweeen the Mac and the printer. The scan function has started working on the first Mac after I repositioned the printer vrey slightly, yet a second Mac on the same desk as the first with the same version of MacOS is still giving error -9923, but will print. How can a Mac print wirelssly to a printer but not scan? What is different about the wireless communication? I will update the firmware on the second Mac to see what happens.
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