When printing solid blocks of colour, the printer leaves white horizontal lines inside them. This is especially noticeable in "Normal" or "Draft" printing modes; it's not as bad in "Best".
So I tried doing a cleaning of the print heads (using the HP Smart program on the computer), but that has not helped: the stripes remain.
I tried to take a look at the print heads themselves, but the printer won't let me: when I open the front panel, it does not allow me access to the print heads. (It assumes there's nothing wrong with them, apparently.)
I also have the problem that the printer does not print enough yellow. Not just when printing from the computer, but also when making colour copies of photographs (using the scanner): yellow comes out too light compared to the original; orange comes out too red, etc. Could that be the same printhead-related problem, or do I need to make a different post about that?
Thanks for your answer. However, there is no "Show options" on that page. There is only "HP Virtual Agent" (the toy for wasting your time with), and "Message us", which seems to direct me to the UK site of WhatsApp. What am I supposed to to there? Reiterate what the problems are?
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