The smart cell on the label roll is not detected. No label roll is installed, or the roll is improperly installed so that the smart cell does not align with the reader.
The leading edge of the labels or the notch between labels is not detected. The label supply has run out or is improperly installed.
M7, M7C, BM7 or BM7C material is not installed.
Troubleshooting
Install, replace, or reinstall the labels, making sure that the smart cell is properly aligned and that the label supply covers the sensors: M710 - Load Labels and Ribbon.