Downgrading Firmware on HP Officejet 7740 When It's not Recognizing Third Party Cartridges.

All the steps and resources for the files are on my blog post below.
https://mypcjobs.wordpress.com/2020/0...

Here is a new link since my mega link has been removed. I will try to find a way to get mine up.
https://www.ldproducts.com/firmware-d...

I received this printer from one of my customers who bought cartridges from me as well that were third party. HP occasionally updates their Officejet printers firmware at random times to prevent the use of Non Hp cartridges. Another thing to note is that if you purchase a new officejet printer it is set to default to update the firmware automatically once connected to internet.

After some research I was able to find some older firmware updates that would downgrade the printer so that the cartridges could be used again.