On some PCs the error message Failed to open \EFI\ubuntu file not found may appear at startup, although shortly after the message disappears and the system continues to boot normally.

We think it's coming from the UEFI system itself as it processes the provided efi file. It could be that we have initial UEFI support, but no secure boot support, so the default efi file provided by grub-install (\EFI\ubuntu\shimx64.efi for me) can't handle that unexpected case and throws the error.

Running these commands from the terminal (change /dev/sda to your boot disk if necessary) and rebooting fixes the error message for us, but hopefully the grub developers can fix the default to make it work for our strange systems.

sudo grub-install --no-uefi-secure-boot /dev/sda

sudo update-grub

and from the next reboot of your PC the error should no longer appear.

Please see this how-to.

Your system doesn't know your usb/wifi/eth printer or multifuction? No problem. Regiter to our Forum and send us a mail to dev[at]ufficiozero.org with your account information and we will activate your account as soon as possible.

Then open a discussion on “printers repository” section with detail of your printer and if the source code for your driver exists we will release the binary packages into production and you will only have to update your system when advised.