MobileRead Forums - View Single Post - Old Jailbroken Kindle Unable to update software

Bogumis · 03-02-2026, 06:51 PM

I successfully installed the MKK package (got "Update Successful" message), but KUAL still shows "not signed by an authorized developer" error.

Every official update (5.1.0) or custom .bin (hotfix/bridge) is automatically deleted from the root directory the moment I unplug the USB cable.

The search bar commands (;uxtp, ;log, ;otav) do nothing-no reaction at all.

I've tried a hard restart (40s hold) with the update file on the drive, but it didn't trigger an update.

Is there any way to "force" the 5.1.0 update or fix the developer keys on this very early 5.0.0 firmware without a registered Amazon account?

03-02-2026, 06:51 PM	#2
Bogumis Junior Member Posts: 3 Karma: 10 Join Date: Mar 2026 Device: Kindle Touch 3G + WiFi (Kindle 5) B00F	I successfully installed the MKK package (got "Update Successful" message), but KUAL still shows "not signed by an authorized developer" error. Every official update (5.1.0) or custom .bin (hotfix/bridge) is automatically deleted from the root directory the moment I unplug the USB cable. The search bar commands (;uxtp, ;log, ;otav) do nothing-no reaction at all. I've tried a hard restart (40s hold) with the update file on the drive, but it didn't trigger an update. Is there any way to "force" the 5.1.0 update or fix the developer keys on this very early 5.0.0 firmware without a registered Amazon account?