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helloworld1215
November 1st, 2013, 03:48 AM
At installation it did not detect Windows. I mounted the Windows partition and have run os-prober with no results returning.
I am able to boot Windows or Ubuntu by specifying the partition in UEFI boot order. The bios does not appear to allow booting with legacy. SecureBoot is on.
This is with Ubuntu 12.04 LTS on a Inspiron 15.
Here is the gdisk:

1 2048 1026047 500.0 MiB EF00 EFI system partition
2 1026048 1107967 40.0 MiB FFFF Basic data partition
3 1107968 1370111 128.0 MiB 0C01 Microsoft reserved part
4 1370112 2394111 500.0 MiB 2700 Basic data partition
5 2394112 544743423 258.6 GiB 0700 Basic data partition
6 606183424 625140399 9.0 GiB 2700 Microsoft recovery part
7 544743424 545230847 238.0 MiB 0700 (/boot)
8 545230848 556949503 5.6 GiB 8200 (swap)
9 556949504 606181375 23.5 GiB 0700 (/)
When installing ubuntu, I believe I specified that the bootloader be installed on /dev/sda.
I added the following to /etc/grub.d/40_custom but booting ubuntu did not offer a grub menu:

menuentry "Windows 8" {
set root = "(hd0,4)"

chainloader +1

} When booting I think I see "EFI Disk error" flash very quickly before Ubuntu starts booting.

oldfred
November 1st, 2013, 04:56 AM
Grub2's os-prober and your entry are the old style BIOS boot entries that try to boot a Windows partition. With UEFI you chainload to the efi partition to boot Windows.

Boot-Repair will add correct entries to 25_custom.
Unable to chainload Windows 8 with Secure Boot enabled Also post #11 on using refind
https://bugs.launchpad.net/ubuntu/+source/grub2/+bug/1091464

Several examples exist, either using search or specifing the UUID of the efi partition. Bug report above shows those also.



menuentry "Windows 7 UEFI" {
search --file --no-floppy --set=root /efi/Microsoft/Boot/bootmgfw.efi
chainloader (${root})/efi/Microsoft/Boot/bootmgfw.efi
}



After any grub change to get menu updated.

sudo update-grub

If installer did not see Windows at all, did you still have fast boot or the always on hibernation still on. Or is it an Ultrabook with Intel SRT? See links in my signature for more info.