Poor quality print after a print head clean can be caused by a build-up if dried ink in the ink waste unit. The waste unit can be cleaned as shown in this video.
Some HP firmware version prevent the use of Non-HP cartridges please follow these instructions to install firmware which allows their use.
Step 1 - Check Firmware version installed on your printer.You can check that by printing "Printer Status Report" from menu of your printer. If you are unable to do so, because of error messages, follow the instructions to download and install your new firmware.
HP's dynamic security feature can cause error messages to be displayed on your printer.
HP have released new a new firmware version which corrects this fault, please follow these instructions to update your firmware and resolve this issue.
Step 2 - Go to HP SUPPORT WEBSITE and type in your printer modeil number e.g. "HP OfficeJet Pro X476dw MFP"
Your printer needs to ber connected to the computer by a USB cable.
Go to the section "Software and Drivers" on the left-hand side of the website and press "GO" to continue.
The website should automaticalyl detect your operating system.
Now click the "Firmware" button. It will display the latest firmware for your printer.
Follow the instructions to download your firmware update (it should be version 1640 or above).
Step 3 - Install your firmware update directly from the HP support website by following on-screen instructions.
Step 4 - Once the update has finished, you're ready to continue printing