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I'm installing Ubuntu in my asus n56j machine. The idea is that I would have a dual boot machine between Windows 8 and Linux Ubuntu.

I've followed this steps in the bios system, encountered here Booting Ubuntu12.10 USB on Asus X401a Win8

Under 'Security' disable 'Secure Boot Control' Under 'Boot' disable 'Fast Boot', then enable 'Launch CSM', then enable 'Launch PXE OpROM' Save changes and restart.

With previous steps, I get that my ubuntu begin to boot for start the installation wizard, but when I finish the installation, I reboot the system and I see the following

  • Before appear the grub, the system show me the message: "error efidisk read error"

  • When I choose the option Ubuntu for enter to Ubuntu System, I see the black screen.

  • When I choose Windows 8 option loader, I see this message:

    error: Secure Boots forbids loading module from (hd0, gpt8)/boot/grub/ntfs.mod.
    error: no such device: 48C2B8B4C2B8A798
    error: unknown command ´drive map'.
    error: invalid EFI file path
    Press any key to continue ...

This is related to UEFI?

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It seems like secure boot is back on? best to see details. help.ubuntu.com/community/Boot-Info and black screen may be a video issue. askubuntu.com/questions/162075/… –  oldfred Jan 26 at 23:33
I trying with boot repair and this is my report paste.ubuntu.com/6826779 :( –  Bernardo Garcia Jan 27 at 16:50
Only 13.10 and probably 12.04.4 in a couple of weeks have grub2's os-prober that finds Windows in UEFI mode. You can only boot the entries by Boot-Repair, not os-prober. And you have run the Boot-Repair backup & rename which means you can only boot Windows from grub menu entry with bkpbootmgfw.efi in it. black screen issue is then separate. askubuntu.com/questions/162075/… –  oldfred Jan 27 at 17:57
Guys, thanks for your support. I solved the problem installing first Windows from scratch. The Window Installation create by default the UEFI partition of type "boot partition". Then, I proceed with the Linux installation (ubuntu) using this UEFI partition of boot type that WIndows create for my linux installation too, attending the recomendation of this link help.ubuntu.com/community/UEFI#Creating_an_EFI_partition. –  Bernardo Garcia Feb 5 at 21:43
I have been waiting the ubuntu installation process and after finished I'll know that the ubuntu installation not mount grub, so, my list of operating systems not appear, but I solve this problem, executing the boot repair process commented in this other link help.ubuntu.com/community/… The boot repair utility fix my grub and my operating system windows and linux entries is so good. Is a tedious process, because if you update windows 8 to 8.1, your grub don't appear and is necessary make again this process that I describe.Happened me with linux –  Bernardo Garcia Feb 5 at 21:48

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