2

I have a dual-boot Asus notebook and I almost-accidentally deleted every boot option with EasyBCD.

Now I can only load Ubuntu, because there are no more boot options on the Windows partition.

Is there a way to boot on Windows again?

I also have a recovery partition (factory reset from Asus), but I can only access it when the first boot screen from windows appears (pressing F9). I can create a new boot option at BIOS, but I don't know what to put on the EFI file patch there. There's some .EFI files on the recovery partition...

Journeyman Geek
  • 127,463
  • 52
  • 260
  • 430
Ricardo Martins
  • 131
  • 1
  • 6
  • Try in Ubuntu execute `sudo update-grub`. It will attempt to find and add all the operating systems it can find. The problem is whether or not you're using the Windows bootloader itself to load Grub. If so, get a Windows disc (or boot to Win RE if it's available), open a command prompt, and type `bootrec /RebuildBcd`. See http://support.microsoft.com/kb/927392. You may have to recover the Grub option after doing this. – cyanic Sep 27 '12 at 02:31
  • I ran update-grub, but when select _Windows 7 (loader) (on /dev/sda3)_ it says: error: invalid EFI file path Press any key to continue – Ricardo Martins Sep 27 '12 at 14:59
  • @GMMan I also tried to use a windows 7 home installation on USB, but at installation setup the option to recover does not appear. I've continued the setup until a step that shows all of my partitions but windows said that cant install on each of them because the file format of them. I guess windows 7 was installed using EFI, so I cant recover using the installation cd. – Ricardo Martins Sep 28 '12 at 11:50
  • The Windows DVD can be boot from EFI. You just have to find the right option from your BIOS to do so. You should be able to press a key to choose the boot device, and depending on the manufacturer it could have separate options for EFI and regular. Also check the BIOS to see if you can use EFI for booting from the optical drive. – cyanic Oct 04 '12 at 00:40
  • I recorded the image on pen drive and tried to boot using efi, but it doesnt work. It only boots by the usually way (without efi) – Ricardo Martins Oct 04 '12 at 11:36
  • Here's something I found: http://forums.bit-tech.net/showthread.php?t=209045. If your BIOS does not support EFI boot from USB, you might be able to load an EFI environment using an EFI emulator like iBoot. – cyanic Oct 05 '12 at 12:14

1 Answers1

1

Try repairing Windows BCD using bcdboot.exe.

You should boot Windows Recovery/Installation media (USB/DVD) using EFI boot - check firmware settings.

There is no active partition when using EFI/GPT boot method, instead there is a special EFI System partition which is involved in the initial boot process.

snayob
  • 4,384
  • 1
  • 16
  • 22
  • where can i find a windows recovery media? My notebook doesnt come with any cd. I have a 10gb partition for recovery, but I cant select this to boot. The partition only appears when windows is booting normally and I select the recover option on F9 menu. – Ricardo Martins Oct 02 '12 at 11:27
  • You can transfer recovery partition to USB (copy all files). Use a Windows 7 Installation DVD (see link given above), go to recovery command prompt and use diskpart.exe, bootsect.exe and bcdboot.exe to make the USB bootable. – snayob Oct 07 '12 at 04:44