If the downgrade was successful, you may need to clean the cartridge chip contacts or perform a "Factory Reset" via the Support Menu.
Older firmware versions are susceptible to known exploits. Specifically, the 8620 was affected by vulnerabilities cataloged as:
Attempting these methods is extremely risky and is strongly discouraged for several reasons:
HP updates are designed to improve performance, but they frequently include "security" patches that: hp officejet pro 8620 firmware downgrade
If you can tell me the you're seeing and who manufactured your ink , I can provide more specific advice. Alternatively, I can help you find a compatible firmware file or guide you through a factory reset if that would be more helpful. HP Printer Firmware Downgrade Guide: Download Link Included CompAndSave
: Ensure the printer is in a "Ready" state. If it is stuck on a cartridge error, you may need to temporarily install at least one genuine HP cartridge to access the menus. Firmware File
Before you downgrade, you must stop the printer from automatically re-updating itself. If the downgrade was successful, you may need
How to Downgrade HP OfficeJet Pro 8620 Firmware If your HP OfficeJet Pro 8620 suddenly stopped recognizing third-party or refilled ink cartridges, you are likely a victim of "Dynamic Security." HP often pushes firmware updates that lock out non-HP chips. To regain the ability to use more affordable ink, you must downgrade your firmware to a previous, less restrictive version. Why Downgrade Your Firmware?
HP does not officially host older firmware. You must find a version that predates the security lockout (such as or 1640A ) from reliable third-party archives or community threads.
Downgrading the firmware on an HP OfficeJet Pro 8620 to bypass "cartridge error" messages requires finding an older firmware version (like FDP1CN1910AR or similar) and flashing it via USB, as HP officially discourages downgrades. Alternatively, I can help you find a compatible
You may need to use a Windows 7 or Windows 10 PC, as newer security frameworks in Windows 11 sometimes block low-level firmware manipulation tools.
HP provides an official, safe, and supported firmware update that specifically removes the Dynamic Security feature for OfficeJet Pro 8620 printers. Here’s how to do it: