I have an OfficeJet Pro 8600 that was purchased in the USA...but for the past 4-years we have been living in Costa Rica and using cartridges procured locally. We are now back in the USA and with new cartridges (regional code Z10), I am now receiving an error message that the cartridges are not compatible. They are the HP 950 (black) and 951 (color) cartridges...purchased from Best Buy.
All of my early research recommended cleaning (done...did not work) and a Regionalization Reset. Help?!?!