Why is my HP printer not printing certain lines?
Make sure that each ink cartridge is firmly in place in its slot. Run your finger along the top of the ink cartridges to feel for any that are protruding, and if any are, press down firmly until each ink cartridge snaps into place. Close the ink cartridge access door. Try the print job again.
Why is my HP printer printing patchy?
HP printheads clog periodically as small amounts of ink or dust dry up and collect in the nozzle. Faint, streaky or spotty prints are all common signs of a clog but a simple cleaning can usually get your HP ink cartridges working again. Printheads clog due to infrequent cartridge use.