No. Usually you can’t fix the problem once the lines remain over more than 1-2 prints. Problem is the print head of course. The real question is WHEN does it happen and WHY. In my case (Officejet Pro 8620) the lines started appearing immediately (!) after placing non-HP catridges to the printer when out of warranty. This is actually very unlogic from a technical point of view, as there still is original ink in the print head. That’s why MANY SAY and so I do believe that the problem is “caused” programmatically. So you would need to buy a new printer or at least print head. PROBLEM. There is no real proof for what I claim or believe. Why? HP can argue differently and we can’t look into the internal communication of the print head, main board, etc. but I’m actually thinking of doing that, because it is possible with the right knowledge and someone should check against fraud.

Replacing easy.

BUT. Can it be repaired? Someone real experience with it?

PS. Of course only as no physical damage from outside and all 4 ink chambers (1) still sealed properly and (2) never have run empty