HP Released a Firmware Update to 8600a N911, Now I can't print!

[VailEnterprises]

My printer worked fine until 2 days ago. I noticed a undocumented automatic firmware update was running on the printer's display screen on the 10/21/20. After this "update", I can no longer print from to the printer from my PC when using a network connection. The HP Smart App shows it's connected to the printer and I am able to scan from that app, but printing is totally dead. The jobs just que up on the PC and never print. The error message "Printer Offline" appears when printing. I deleted the printer in the Windows 10 settings screen in order to re-add it and it can no longer find it. I checked the support page for my printer and it doesn't even show the new firmware is available for download! The version of the firmware according to the printer's reporting feature is: CLP1CN2011AR.

I downloaded the previous version of firmware but the when running the installer for it, it doesn't even see the printer, yet the HP Smart app does and allows me to scan from the printer so I know it's connected and on the network.  I am able to print using a USB connection to the printer and when using a USB cable to restore the old firmware, the firmware program sees the printer but says it's status is unknown. When it has an unknown status, the firmware program won't let you execute the program for the printer. I'm stuck for now. I may return with more details later. For now, this is just to let everyone else having a problem know it's not just them.

- UPDATE: RESOLVED! I reset the network settings on my printer, reset my Asus wireless router, and reset my ATT Fiber Modem. After doing these things, I was able to re-add the printer to Windows 10 and it now prints. I suggest doing these steps if you experience the problem I listed above. GOOD LUCK!

[hb020]

Initially same issue here, on a Mac Catalina 10.15, and having the latest HP software.

What worked for me:

1. remove the printer from MacOS
2. reinstall latest HP Easy Start (in my case: June 2020). Do not add the printer, it will not work. (This step may not be needed, but anyway)
3. shut down both Mac and printer (pull the power cord on the printer)
4. restart both
5. install the printer using the Airprint driver (NOT the HP Officejet Pro 8600 driver, it blocks)

and it works. The moment you try to use the HP Officejet Pro 8600 driver, everything blocks again, and a removal of that printer and a reboot of both devices seems to make it work again.