Click . The printer screen should show that it is updating.
No. The unsigned .rfu file requires Windows’ raw USB stack. Macs add extra validation layers that HP exploits to block downgrades.
If this option is grayed out or missing, it means the current firmware has locked this setting. In this case, you would need to buy original HP cartridges or attempt the downgrade above.
Legal and warranty notes
If the process seems too risky, consider these options instead of fighting HP’s firmware war:
The printer's display will show an update in progress; during this time. 3. Disable Automatic Updates Post-Downgrade
Phase 3: Making the Downgrade Permanent (Preventing Future Issues) hp officejet pro 8620 firmware downgrade new
: Use a direct USB cable connection between your computer and the printer rather than Wi-Fi to ensure stability during the process. Step 2: Obtain Legacy Firmware
HP OfficeJet Pro 8620 Firmware Downgrade: Guide for 2026 Downgrading the firmware on your is often necessary when a recent update prevents the use of more affordable third-party or compatible ink cartridges . While HP frequently releases updates that include "dynamic security" to block non-HP chips, rolling back to an older version can restore compatibility and save on printing costs. Why Downgrade Your HP 8620 Firmware?
Prevent the printer from accurately displaying ink levels for refilled cartridges. Step-by-Step Downgrade Process The unsigned
A: This usually indicates the firmware on the printer is newer or configured differently (region-locked) than the file you are trying to flash. In most cases, the standard HP Updater cannot force this change; you would need an advanced method.
As of March 2025, . The remote downgrade exploit via telnet (used in 2022-2023) is patched. The USB recovery method is the only active vector.
If it’s , you are a candidate for downgrade. In this case, you would need to buy