This problem is caused by dried ink. The ink cartriges or the cartridge carriers are caked with dried ink, either inside or on the outside. You need to physically clean the cartridge nozzles (usually silver) and the cartridge electronic board (usually gold) with a rubbing alcohol wetted paper towel (removing the dried ink) OR To clean the electronic boards (usually gold) on the cartridge carrier (where the cartridge mates against), using the a similar alcohol wetted paper towel. If physical cleaning does not fix it ( 85% says it will) then you need to run thru the printer deep cleaning procedure or buy replacement cartridges. ZT3000 "Beta tester of "0"s and "1's"
This could happen for a number of reasons. The worst case could mean a malfunction that will require service but there a few things to try before jumping to such expansive unpleasent conclusions: 1. Use the Hp tools to clean the cartridges and realigh the device 2. You may want to try to physically clean or even replace the ink cartridges. they are known to brake and cause such symptoms. Try to borrow a cartridge from friend to test the device before spending money. Good Luck
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