1) Open door so print heads move to the center
2) Unplug the unit. (Don't turn off, just unplug!)
3) Open back door
4) Look inside the back left side for a small black gear (About the size of a quarter)
5) Spin the gear with a screw driver (I'm pretty sure I spun it clockwise). Spin it and watch the inside of the printer where the print heads park. You should see a tray move out that has four rubber blue rectangles on it on the right side of the unit (this is where the print heads park when the unit is not printing).
6) Keep spinning the gear until the plate moves all the way forward.
7) Grab the plate and try moving it forward more.
8) Put the back on and close the top.
9) Turn the unit back on.
10) Open the top again
11) Unplug the unit again. (Don't turn off, just unplug!)
12) Grab the tray, from step 5, and slide it all the way forward and all the way back multiple times.
13) Make sure that the print heads slide left to right smoothly
14) Remove ink cart's and clean the contacts with bottled water and a q-tip. LET DRY BEFORE REINSTALLING!!!
15) Remove print heads and clean contacts with bottled water and q-tip. LET DRY BEFORE REINSTALLING!!!
16) Clean the inside of the printer with a soft dry cloth, use a slightly damp, with bottled water, lint free cloth (Glasses cleaning cloth works well) and wipe off the rollers in the front and back of the unit. See HP's cruddy support site for details on this step.
17) Hold down #7 (reprimes the printheads with ink) and plug in the unit
If needed also turn off and do a #6 to reset the unit.
http://h10025.www1.hp.com/ewfrf/wc/document?docname=c01814862&lc=en&dlc=en&cc=us&product=3793939
Follow the mentioned web page as well for help but select your product.