21F0
Cause
Force ink tank selection is set to Black only, but one or more of the current print settings are incompatible with this selection.
What to Do
When Force ink tank selection is set to Black only in the printer, you can only specify printing on plain paper / envelopes, and bordered printing on hagaki.
To print with the current print settings using other ink colors as well, select OK on the printer's touch screen. The printer starts printing.
To print using only black ink, press the printer's Stop button to cancel printing, change the print settings, and then retry printing.
