08-09-2013 06:42 PM
If you are having a print quality issue with the Officejet 4620, then I would advise taking a look at the steps in the document linked below.
If the steps do not address the issue, then keep in mind that the printer comes with a 1yr factory warranty. If you got this printer only 6 months ago, then the printer is still in the manufacturer's original warranty period.
I am not an HP employee.
08-10-2013 06:00 AM
The cause remains a mystery. The solution was to remove the cartridges and put them back in. We suffer frequent transient power outages. I had to remove and reinstall several times.
I have since gone through several sets. The problem has not reoccured. I do not think the problem lies in the printer but something in that set of ink cartridges.
The diagnostics could offer more 'in the weeds' detail for those of us who would welcome it. Or a big reset button - a simple reset likely would have solved the problem.