In the same menu, set Check Automatically to Off to prevent the printer from re-updating itself immediately after the downgrade. Phase 2: Obtaining Old Firmware
If you want to ensure this process goes smoothly, please let me know: What your computer runs (Windows or Mac)? hp officejet pro 8620 firmware downgrade
Temporarily pause your computer's antivirus program and Windows Defender firewall, as they can block the firmware flashing utility from communicating with the USB port. In the same menu, set Check Automatically to