You know it’s time to change your printers ink cartridge when the quality degrades or you start receiving the low ink alert messages. Here’s a step by step tutorial on how to replace ink cartridge on HP Office Jet Pro 8600. After turning on, open the printer’s outer lid and print cartridge access door. Wait until the printer is in idle mode and the press down the old cartridge to get it released. Replace the new one in the slot. Make sure you do not touch the new ink cartridges. Close the lids of the printer to complete the process and test print.