So did Apple replace the Xerox driver with their own? Because the fault typically happens due to Calibri fonts and old drivers, and you can't be printing nothing but Calibri font files from "every program and every type of file"
So if the driver is showing Kind as Generic PS, or Airprint or really, anything but a Xerox 7100, it could be the problem, even if you have the right driver on the System, it doesn't mean Apple is actually using it. (screenshot for example, not the right machine)
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