On Tue, Nov 20, 2018 at 7:40 AM lejeczek via CentOS <centos at centos.org> wrote: > hi guys > > I have a box on which UEFI boot has gone haywire and instead > of boot it power the box down, that is before even going to > grub2. (displays some error message) > I if change to BIOS boot then I can start Centos' rescue - > my question is: how can I rescue, re-build grub so it would > boot from tradition BIOS? If the OS was installed with UEFI enabled I would go back to UEFI mode. Then re-add your OS boot configuration within the BIOS setup screen. Most motherboard manufacturers detail this process on their website where you browse the disk to select somefilename.efi and give it a label “CentOS”. >