Grub unable to detect Windows [SOLVED]

[luayessa]

I installed Linux Mint 17-64 bit on a PC that already has Windows 8. During the installation, the Grub was not able to detect Windows 8.
The installation completed successfully, however now I am not able to boot into Windows.

I installed Boot-Repair but it did not help. I noticed that I can select Windows 8 as the default OS from Boot-Repair, but the Windows 8 is not found in the Grub menu.
I tried the following command: os-prober, but the output was: No volume groups found only.

The following URL has the Boot-Repair log file:
http://paste2.org/nAeJOMnU

I also attached a screen shot of the GParted

Can you help please?

[gtsfer]

Did you try "sudo os-prober" from a live boot session? Here's a link with some info on installing dual boot with W8 (maybe a little late as you've already installed, but it might help). http://forums.linuxmint.com/viewtopic.php?f=42&t=163126.

It appears that your W8 partitions are all still there from the screenshot. Boot up in live mode and try the command again if you can do that.

[PatH57]

Hi,

you did what shouldn't have been done during the first setup of Mint

Question: Why GRUB is not installing properly in my machine?
Answer: New machines have EFI capable bios. This means that by default MS Windows is installed in UEFI mode and this requires a GPT formatted Hard Disk. At the present GRUB cannot install itself in GPT partition table without a huge effort and special skills.

[luayessa]

I don't have much information about EFI or GPT. It seems the Windows boot files were deleted, but the Windows OS files are still there. I will try to reinstall the windows boot files again. Thank you.

Hi,

you did what shouldn't have been done during the first setup of Mint

Question: Why GRUB is not installing properly in my machine?
Answer: New machines have EFI capable bios. This means that by default MS Windows is installed in UEFI mode and this requires a GPT formatted Hard Disk. At the present GRUB cannot install itself in GPT partition table without a huge effort and special skills.

[PatH57]

make a backup first of your data, windows has a bad habit of wiping the drive before it installs.

[luayessa]

I tried from a live boot session but without success. The

Code: Select all

os-prober

still prints:

Code: Select all

No volume groups found

only.
Thank you for the link.

Did you try "sudo os-prober" from a live boot session? Here's a link with some info on installing dual boot with W8 (maybe a little late as you've already installed, but it might help). http://forums.linuxmint.com/viewtopic.php?f=42&t=163126.

It appears that your W8 partitions are all still there from the screenshot. Boot up in live mode and try the command again if you can do that.

[lostfarmer]

Your first problem is that linux was not installed in EFI mode. If it was there would be an entre in your "sda8/etc/fstab:" to mount the EFI partition and you would have the correct EFI files.

2nd problem , your EFI partition has been messed up. It should have the 'boot' flag not the 'bios_grub' flag.

Code: Select all

1 1049kB 525MB 524MB EFI system partition bios_grub

The boot files for Win8 have been deleted and replace by the incorrect Grub2's core.img .

Do a web search for "rebuild win8 efi partition".

Once the Win8 efi partition is correctly rebuilt then you will need to run from a live cd the 'boot-repair' command to install linux efi boot files.

[luayessa]

Dear all,
The problem was solved
I did the following:
1- format the first partition (dev/sda1) as FAT32.
2- using a commercial tool, I re-installed the Windows 8 Boot Files. (I think this can be done using bootrec commands)
3- Now I can boot into windows normally, but the Grub menu is not shown, so I was not able to boot Linux Mint.
4- I changed the BIOS settings to use UEFI mode only (without Legacy option). Also the Boot Security option is off.
5- Using a live USB Linux Mint, I used the Boot-Repair tool to rebuild the Grub menu. I selected the "Recommended" option. I Boot-Repair said there was an error during the Grub building.
6- I restared my PC and now I can the Grub with option to go to Linux or Windows.

Thank you .

[luayessa]

You are right, my problem was installing Linux in Legacy mode instead of EFI mode.
Thank you. I solved my problem.

Your first problem is that linux was not installed in EFI mode. If it was there would be an entre in your "sda8/etc/fstab:" to mount the EFI partition and you would have the correct EFI files.

2nd problem , your EFI partition has been messed up. It should have the 'boot' flag not the 'bios_grub' flag.

Code: Select all

1 1049kB 525MB 524MB EFI system partition bios_grub

The boot files for Win8 have been deleted and replace by the incorrect Grub2's core.img .

Do a web search for "rebuild win8 efi partition".

Once the Win8 efi partition is correctly rebuilt then you will need to run from a live cd the 'boot-repair' command to install linux efi boot files.