What does it mean when the error icon and one or both printhead icons are blinking together?

This indicates a printhead problem — the left printhead icon flashing shows an error with the tri-color printhead, and the right icon flashing shows an error with the black printhead. If you are setting up the printer for the first time, make sure you have removed the tape from the indicated printhead. If you have been using the printer and are experiencing print quality problems, the indicated printhead needs to be replaced; contact HP support at www.hp.com/go/support.