Brother DCP-9040CN Service Manual page 314

(3) Check the port (USB) that the machine is connected through and click "Serial No." in
the lower box.
Enter the serial number (the last nine digits) of the machine into the box on the right
hand side and click the OK button.
A confirmation window opens and shows the serial number. Check that it is correct
and click the OK button.
Note:
Refer to "Appendix 3 SERIAL NUMBER SYSTEM"
number of the machine.
Performing the Auto Registration
Select "Printer", "Auto Regist." and "Registration" from Menu and perform the auto
registration.
to know how to read the serial
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