this unit and 7410, may come with manufacturing defects
please check following link:
http://h10025.www1.hp.com/ewfrf/wc/document?docname=c00304007&lc=en&cc=us&dlc=&product=391164
http://209.85.173.132/search?q=cache:dgwx7YIgaLgJ:forums11.itrc.hp.com/service/forums/questionanswer.do%3FthreadId%3D1160955+mydeadHP7410&hl=en&ct=clnk&cd=3&gl=us
http://www.fixyourownprinter.com/forums/inkjet/50913#1
http://www.fixyourownprinter.com/forums/inkjet/50913#11
http://www.fixyourownprinter.com/forums/inkjet/46650
HP is very honest that replace whole unit with another refub even it is out of manufacturing warranty for one month.