Cannot Boot To BIOS Setup (F2) or One-Time Boot Sequence Options (F12)

I have tried all these and still can't get into BIOS setup or One-Time Boot Sequence.

1. First off, F2 or F12 does not work.
2. F2 right after the keyboard light comes on.
3. Continuous tapping of the F2 key, will cause the desktop not boot at all.
4. Continuous tapping of the F12 key, will cause the desktop not boot at all.
5. Cannot flash the BIOS to a more current version since F12 will not work to select the USB.
6. powercfg /h off
7. Disabled Fast Startup.

8. https://www.dell.com/support/article...system?lang=en

9. Four Methods to Access UEFI BIOS Setup in Windows 8/10 PC/Laptop/Tablet

10.

On many laptops, to access the F1 through F12 keys you need to press and hold the "Fn" key while pressing the function key. This is because these keys often serve 2 purposes. For example, in addition to serving as the fucntion key, the same key may adjust volume, screen brightness, keyboard backlighting, etc.

Try press Fn + F2 or Fn + F12 and see if that works.

I know you are using a TowerPC and not a laptop, but this may still apply.

hsehestedt said:

On many laptops, to access the F1 through F12 keys you need to press and hold the "Fn" key while pressing the function key. This is because these keys often serve 2 purposes. For example, in addition to serving as the fucntion key, the same key may adjust volume, screen brightness, keyboard backlighting, etc.
Try press Fn + F2 or Fn + F12 and see if that works.
I know you are using a TowerPC and not a laptop, but this may still apply.

But desktop keyboard don't have the "Fn" key!

I had this problem with my dell laptop. It is an option in the bios which poses a problem but I do not know which option. Perhaps "Enable Legacy Operation ROMs" which by default should be disabled.
Access the bios from windows and restore the default values by remembering the values that you have changed and that you will reset after testing F2 and f12.


Same as your link:
How to enter UEFI (BIOS) on Windows 10 PCs | Windows Central

When you shutdown Windows, hold down the Shift key when you click on shutdown. This bypasses Windows 10 Fast Startup which interferes with getting into BIOS settings.

caxtin said:

But desktop keyboard don't have the "Fn" key!

Then this does not apply to your system. a few desktops do have the Fn key, but it is admittedly not common.

Bastet said:

What’s the make of the external keyboard? I’ve never heard of any keyboard without a Fn key.

Almost all desktop keyboards have no Fn key.