Thank you so much for this post, I had the CODE D04-534 occur on some of the brand new original cartridges and have been puzzled why they did not work. I tryed the following on my Risograph RZ-390UI and it worked:
go into test mode..
turn off machine and turn it back on while holding down the left and right print position arrows.
if the error code shows up.. press the yellow reset button to clear it.. you will then see a number (firmware ver.) press the "C" button on the number pad..
you should then see the display all zeros "0000"
enter 890 and press start.
then when it beep press the "C" again enter 112
when it beeps again press and hold the yellow clear button and the machine will reboot...
HOPE THIS WORKS ON YOURS... Thank you so much for this post, I had the CODE D04-534 occur on some of the brand new original cartridges and have been puzzled why they did not work. I tryed the following on my Risograph RZ-390UI and it worked: go into test mode.. turn off machine and turn it back on while holding down the left and right print position arrows. if the error code shows up.. press the yellow reset button to clear it.. you will then see a number (firmware ver.) press the "C" button on the number pad.. you should then see the display all zeros "0000" enter 890 and press start. then when it beep press the "C" again enter 112 when it beeps again press and hold the yellow clear button and the machine will reboot... HOPE THIS WORKS ON YOURS...