In case your HP Envy 4520printer device is not recognizing ink, then you will have to follow the below set of steps to fix the issue. We have made these steps simple and easy for you to understand and follow.
⦁ Firstly you will have to turn on your HP Envy 4520 printer device.
⦁ Then you will have to open the access door.
⦁ Wait until the cartridge becomes idle without making any noise.
⦁ Then you will have to open the cartridge slot.
⦁ Remove the ink cartridge from the slot.
⦁ Check for any protective tapes in the ink cartridges.
⦁ If you find any tapes, you will have to remove the protective tapes.
⦁ Once removed reinsert the ink cartridge in to the slot.
⦁ Now close the cartridge slot.
⦁ Then you will have to close the access door.
⦁ Once you are done try to take print outs and check whether the issue has been cleared.