Please follow this instrution mention from the below url
http://h10025.www1.hp.com/ewfrf/wc/document?docname=c01892627&cc=us&lc=en&dlc=en&product=79499
if still it not work then try this URL mention from the below
http://h10025.www1.hp.com/ewfrf/wc/document?docname=buu01831&tmp_track_link=ot_recdoc/c01892627/en_us/buu01831/loc:3&lc=en&dlc=en&cc=us&product=79499
after try this if still not resolvce then follow this step
1)disconect the power cable from the wall outlet
then press and hold the power botton for 20-30 sec then restart and try to print test page
if still it does not resolve your issue then contact HP toll free number 1800-474-6836 they will replace your printer if it under warrantry

thanks
regards
Hamid