Unable to start Windows - UEFI boot problems with Linux + Win8

Question

I have installed openSUSE (12.2) on a PC that has Win8 installed.

At the beginning there were problems and it didn't start, after some "fixes" Linux started but when going in the grub2-efi Windows 8 entry I get this error:

error: can't find command 'drivermap'
error: invalid EFI file path

First of all, I have checked and in my /boot/EFI/ there's no Windows .efi file, just the openSUSE one.

I have tried the command:

grub2-efi-probe --target=fs_uuid /boot/efi/EFI/Microsoft/Boot/bootmgfw.efi 

and I got:

grub2-efi-probe: error: failed to get canonical path of /boot/efi/EFI/Microsoft/Boot/bootmgfw.efi."

I tried also to modify /boot/grub2-efi/grub.cfg, adding:

menuentry "Windows 8 UEFI" {
  insmod part_gpt
  insmod fat
  insmod search_fs_uuid
  insmod chain
  set root='(hd0,gpt4)'
  search --fs-uuid --no-floppy --set=root 4f84-ee2e
  chainloader (${root})/efi/Microsoft/Boot/bootmgfw.efi
}

as suggested in some websites..

I also tried:

menuentry "Microsoft Windows Vista/7/8 x86_64 UEFI-GPT" {
  insmod part_gpt
  insmod fat
  insmod search_fs_uuid
  insmod chain
  search --fs-uuid --set=root $hints_string $uuid
  chainloader /EFI/Microsoft/Boot/bootmgfw.efi

}

but no luck.

My guess is that the Win EFI file has been deleted and I need that to make Win start? Am I right?

In this case, where can I find it? Is it possible to solve this problem without reinstalling Windows (I've got no DVD)?

Edit:

sudo ls -l $(find /boot/efi -iname "*.efi")
root's password:
-rwxrwxr-x 1 root root 665600 Jan  8  2013 /boot/efi/EFI/opensuse/grub.efi
-rwxrwxr-x 1 root root 120832 Mar 11  2013 /boot/efi/EFI/opensuse/grubx64.efi

Answer 1

The second of your two GRUB configuration entries is closer to being correct. The example I generally present looks like this:

menuentry "Windows" {
    insmod part_gpt
    insmod chain
    set root='(hd0,gpt1)'
    chainloader /EFI/Microsoft/Boot/bootmgfw.efi
}

Your example is missing the set root line, which you'll need to customize for your system. (It should point to your EFI System Partition (ESP).)

Alternatively, you could boot into Linux and install the RPM version of my rEFInd boot manager. rEFInd is much less finicky than GRUB, and it's easier to manage its configuration manually; but as it's not officially supported by OpenSUSE, you're more likely to have to manually configure it. (Of course, you're at a point where you're being forced to manually configure GRUB, so that may not really be a disadvantage of rEFInd!) One caveat about rEFInd: If you're booting with Secure Boot enabled, you may need to tweak the Secure Boot configuration. In particular, I've recently discovered that the Fedora and OpenSUSE versions of shim use different filenames, so you may need to play with those or disable Secure Boot in your firmware.