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Here's the solution to reset the MP 150

1) First power off the printer. Next, while holding STOP/RESET button, power on the printer.

2) While holding POWER button, release STOP/RESET button. Then push STOP/RESET button twice.

3) Wait about 20-30 second until the LED shows "0". The push STOP/RESET button four times.

4) Finally push POWER button twice. Last step is to turn off the printer by pressing the POWER button one last time.