: Look for a firmware version known for compatibility, such as or earlier.
Here is a comprehensive guide on why downgrading is better and how to do it safely. Why Downgrade Your HP 8620 Firmware? hp officejet pro 8620 firmware downgrade better
Downgrading is not without risk. Read these warnings carefully. : Look for a firmware version known for
Downgrading an 8620 is not a simple "undo" button. It requires a deliberate, semi-hacktivist process: semi-hacktivist process: Before you start
Before you start, note that HP does not officially support downgrading and often removes old firmware files from their site.