This error occurs because the printer is "Searching" for labels to print on.
To fix this:
1. Open your printer and find the yellow plastic tab at the very front that slides back and forth.
2. On this tab you will see an arrow.
3. On the printer you will also see an arrow and several lines.
4. Slide the yellow tab so that the two arrows line up.
5. Calibrate your printer and do a test print.