HP Probook 4545s, came with Win8 installation.
First installed Ubuntu onto sparate '/' partition; after restart system rebooted into Win8 (no GRUB whatsoever). Then ran boot-repair for the first time - now system finds no bootable image; after powerup is displayed '>>Start PXE over IPv4.', followed by '>>Start PXE over IPv6.' after which system shuts down. Guess it tries to boot over the network, but obviously fails to do so.
Then returned to the tutorial, where discovered UEFI needs separate bootable partition. From the first boot-repair report it looks as if grub got installed into correct EFI partition nevertheless, but just in case ran repair again, defining the GRUB location onto the EFI partition.
Welp, still the same. It should be added I'm not 100% sure whether Fast boot is disabled, since the tickbox in BIOS is disabled, but comment says it would be disabled when DriveLock gets enabled, which it is. Secure boot is disabled.