How to enable the legacy boot, that can't activate before disable secure boot (while i just disable it).

Is your BIOS UEFI?  Likely. If so, and if you need to boot from USB, just disable Secure Boot temporarily.

The prior reference above was from 2007 and has nothing to do with today's systems.

yes, UEFI BIOS.
I need the legacy bios, because the program i want to install Requires it.

You would have to revert UEFI to legacy. Can you not use a different computer?  And what program needs a specific BIOS format?  I do not run across this (at ANY client or myself).

the program linux base.
run in dual boot, may install to Harddrive, or instal via LAN.
(im sorry for my bad english)

You can run Linux with UEFI and Secure Boot:

https://www.linux.com/learn/how-install-linux-windows-machine-uefi-secure-boot

I really do not recommend going back from UEFI.

i don't want to change to bios, i just want to enable the legacy boot.
i think that's occurs in some PC,
because the other one solve it.

(comp lab in my school have some of this PC Type, just one of them can enable the case)

I'll try tomorrow, thank you very much.

No comment has been added to this question in more than 21 days, so it is now classified as abandoned.

I have recommended this question be closed as follows:

Accept: John Hurst (https:#a42264843)

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