No diskette update (X41 Tablet)

[jlv]

X41 Tablet bios and/or embedded controler cannot be updated.

The no-diskette procedure fails (with no error message: the system just reboots normally).

The battery is fine and 100% charged, AC on, antivirus fully uninstalled (not deactivacted only). All other software automatic updates work fine and the computer is otherwise fully functional.

Is there any way around this?
Many thanks