ich möchte meine Lösung hier posten, da sie vom moderierten HP community immer wieder gelöscht wird. Der HP passt diese Lösung wohl nicht ganz. Jedoch das ganze auf ENG, es sollt ja die ganze Welt was davon haben...:
! As a special note, this solution is permanently deleted from hp websites, may this post also not long exists. Such thing happens to the "truth" under HP restrictions and regulations - what a mess.
First of all, in my opinion it's an illegal and of course unacceptable thing that HP blocks third party cadridges in the name of an security update called "Dynamic Security" (see and search for c05308850). And naughty to to this in a business product.
Especially the lie of official hotline "theres no way to downgrade". This should be reason enough to never buy HP printer again.
But here solution you searching for - Found via reverse engineering:
In my case, my goal was downgrade to firmware 1848A (WMP1CN1848AR) from 1919BR (WMP1CN1919BR).
This is the solution to firmware downgrade HP Office Jet Pro 8720 and of course 8710 and other series.
First, dont waste your time with the firmware update utility. You already know, that if the installed firmware is newer than the one you try to install, the options are greyed out. It is only possible to update not downgrade with it.
However if the utility is startet from an extracted path, you will notice the file EnterpriseDU.ini in the root path and another one in the folder with the firmware's name. In the file from the first place, you will see VerifyDownloadID=1 inside the ini. If you modify to 0 and start the tool, you get an error message invalid configuration file or similar. But if you change to 0 while the tool is running, then press refresh inside the tool you can select to upgrade (downgrade in this case). But in my case the "update" still fails. In the file of the second path, i notice a list of devices/firmwares under the section [DownloadID]. It seems to be a numbered list of previous firmware states the update tool let you upgrade from. So i try to add additional listings with my actual firmware image, in the hope, the update utlility regonize the "new" als an "older from" image. But i didn't come into the type of hash they used to build from the xy.fh file. So i cancel this investigation. (anyway you will notice the firmwares entry in the same file from future releases).
FINAL SOLUTION: At last, the simple trick to downgrade was shocking easy.
1. On your Windows device, share your printer with simple name, eg. "8720" and dont use spaces or something like that.
(in addition i gave the control printer right to everyone at the share permissions, but maybe this was not neccesary)
2. Press WIN+R -> cmd -> To start a command line (cmd)
3. Switch to the directory where you extract the firmware update file xy.exe and go to the directory where the *.fh file (thats the firmware file) is.
4. Use the following command, to binary-copy the firmware file to your printer (in my case it was a network printer, i dont try usb connection, but i think it would work too)
copy /b weber_vr2_pp1_WMP1CN1848AR_nbx_signed.ful \\localhost\8720
Your printer now making some sounds and updates in the background - dont touch and turn it off now, just wait!
The printer then restarts, shows a green screen, numbered from 1-5, updating and start again.
After update, your before non working catridges will work - what a magic - downgrade works!
In addition, have a look at your printers Web-GUI after upgrade for a function called "Cartridge Protection" at Tools -> Product Information -> Catridge Settings. Turn it to off.
Of course it would be a good idea to turn of automatic update too :-)... look at Tools -> Printer Update -> Firmware Update and turn it to off.
Because HP deletes previous verions from their repository to prevent downgrades, you have to search for the files in the web. The 1848AR firmware file found here (try yourself as long as this link works): https ://hpsetupdriver. com/hp-officejet-pro-8720-firmware-setup/
(Maybe this link above is not shown, this relies on the moderator of druckerchannel.de forum.