MB2100 series (PDF) User Manual (Windows)

Cannot Communicate with Machine via USB
Check1
Make sure printer is turned on.
Check2
Connect USB cable properly.
As the illustration below, the USB port is at the back of the printer.
Check3
Do not start IJ Network Tool while printing. (Mac OS)
Check4
Do not print while IJ Network Tool is running. (Mac OS)
Check5
Make sure Enable bidirectional support is selected in Ports sheet of
properties dialog box of printer driver. (Windows)
How to Open the Printer Driver Setup Window
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