Boox Tab Ultra soft-bricked – need help with firmware / EDL recovery

[Slifer]

Hi everyone,

this is my first post on MobileRead, and I hope I’m in the right place for this kind of request.

I recently bought a used Boox Tab Ultra (black-and-white version, not C or Pro), fully aware that the device had issues booting. It gets stuck during the startup animation – the Onyx logo appears for a second or two, then the screen freezes or goes white.

I can access Recovery Mode, and the device is also recognized via ADB and Fastboot. However, attempts to sideload various .upx and .zip update files fail, and I suspect the issue may be due to an invalid or mismatched firmware file.

I haven’t tried flashing it via EDL yet, as I haven’t found a suitable image for this specific model.

I’m fairly comfortable with technical troubleshooting and would really appreciate any of the following:

-A working update package or decrypted .upx file for the Tab Ultra (non-C, non-Pro)

-Guidance on how to restore the device via EDL or other recovery methods

-Any known tools or community resources I might have missed

Thanks a lot in advance – I’d really like to bring this device back to life.