This message was posted on behalf of Intel Corporation
Thank you for contacting the Intel community.
I’m sorry about the issue you have experienced after the BIOS update.
In this case, let’s try to do a clear CMOS; clearing CMOS might resolve BIOS corruption issues that can prevent an Intel® NUC from starting.
Please follow instructions on how to clear CMOS for this NUC at the following link:
At this link you will see how to move the jumper to 2-3.
It if doesn’t work, we can try a BIOS recovery, please download the .bio file in order to do a BIOS recovery, please follow BIOS recovery instructions.
If the BIOS recovery by the Power Button Menu does not work, scroll down on that same website and follow steps to do BIOS Recovery by the Security Jumper.
I hope this can help.