Verifying shim SBAT data failed:

Question: My bios settings is locked and i don't know the password. How can i turn off the secure boot or is there another way to fix that issue.

ANSWER: Usually, you can reset the Bios password, by

• halting and unplugging the computer.;
• removing the password jumper on the mother board (search for your specific motherboard);
• plugging and rebooting (without the jumper);
• halting and unplugging the computer;
• resetting the password jumper.

While plugging and starting again you will get access to the Bios setting without a password, as well as setting a new password (which is sometimes mandatory).

ANSWER to turning off secure boot on a HP Z4 G4.

I couldn't disable secure boot since years (look at

https://superuser.com/questions/1775652/windows-11-installed-on-a-refurbished-hp-so-that-i-cant-suppress-secure-boot-mo ), but having installed Fedora which requires a Secure boot I have been able to have dual boot working.

The last Microsoft update was forbidding me to access my Linux server.

The procedure was supposed to be easy by setting "Legacy Enable and Secure boot Disable" instead of "Legacy Disable and Secure Boot Enable" nor "Legacy Disable and Secure Boot Disable". After saving this new bios setting, the computer started again visualizing a 4 digits key to enter.

But after entering this temporary 4 digits, the computer started again but kept the "Legacy Disable and Secure Boot Enable" former setting. The solution has been given last November: https://h30434.www3.hp.com/t5/Desktop-Boot-and-Lockup/Cannot-resolve-quot-Selected-boot-image-did-not-authenticate/td-p/8927047 In fact the 4 digits key was entered wrongly and because the bios does not complain, I couldn't imagine a keyboard issue. As explained in the above link the solution consists in entering the 4 digits on the UPPER LINE of the main keyboard and in lower case (as on an English keyboard)!!

Then it is easy to boot on Linux.

Hello,

Did You solve the problem ?

1. Press the power key and keep pressing ESC button till BIOS related menu appears.
2. [In hp] press F9 or BIOS menu and select Windows UEFI to start Windows Operating System .

Note: You have to do these 2 steps every time to start your Windows OS.

Solution: a) Disable Secure Boot in Windows / Ubuntu.

I am thankful for your reply. I had figured out how to start the computer, but I am not able to figure out how to disable the “secure boot” feature. Do you have those instructions? Thank you! Respectfully, David

Success!

Thank you!

Respectfully,

David