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drnagalkar
20th November 2017, 04:59 PM
I was dual booting windows and Fedora on my laptop for the last 10 years using bios. But now switched to laptop with GPT partition table disk. to boot windows and fedora. I have deleted the EFI fat 32 partition 1 while installing Fedora 27 as upgrade of Fedora 26 to Fedora 27 did not work; partition 2 is for linux boot; partition 3 for Fedora 27 LVM, partition 4 is Microsoft system partition, partition 5 is for windows 10 basic and partition 6 is NTFS data.

I did not touch partition 4 ,5 or 6. Now my Fedora 27 is working but grub2 does not recognize the Microsoft system partition on disk. The os-prober of linux kernel also did not detect it.How do I add the Microsoft system partition to EFI partition 1 to make it view-able by osprober? I am not able to boot into windows 10 any more!

Any solutions to make windows 10 bootable using grub2 on Fedora 27?

Please help me.

amiga
21st November 2017, 12:10 AM
I have deleted the EFI fat 32 partition 1 while installing Fedora 27

Why did you do this ? This is the source of your problems. The Anaconda installer typically adds a Fedora directory to the existing ESP or it allows you to create a second ESP. If you delete the existing ESP which contains the Windows EFI bootloader then of course you can't boot Windows.


I did not touch partition 4 ,5 or 6. Now my Fedora 27 is working but grub2 does not recognize the Microsoft system partition on disk. The os-prober of linux kernel also did not detect it.How do I add the Microsoft system partition to EFI partition 1 to make it view-able by osprober? I am not able to boot into windows 10 any more!

You erased the Windows EFI bootloader. How can os-prober detect something that you erased ? os-prober is looking for the EFI bootloader in the ESP and not for the Microsoft system partition.


The os-prober of linux kernel also did not detect it.

os-prober is a script that is called by grub2. It isn't part of the linux kernel.


How do I add the Microsoft system partition to EFI partition

You don't. You have to replace the Windows EFI bootloader that you erased. The Microsoft system partition can't boot the system itself as it isn't a bootloader. It is the EFI bootloader that boots the OS stored in the Microsoft system partition. You may have to re-install Windows unless you have a Windows recovery disk that can re-install the bootloader in the ESP. If you have access to another Windows UEFI computer you could try copying the bootloader files onto a flash drive.

drnagalkar
23rd November 2017, 08:39 AM
Dear amiga,
Thanks for your help.Since I was used to first dos partition to boot either windows or linux in dual boot on bios systems I thought UEFI just records the address to point to windows or linux sector for booting. Thought Microsoft system bootloader partiton contains all files for booting and rest of files in windows 10 basic partition. As linux hanged on upgrade from Fedora 26 to Fedora 27 I wanted to delete UEFI which I thought is a UEFI linux loader as I am used to efibootmgr in Fedora and wondering why the osprobe is not recognising windows.My basic thinking for GPT UEFI was wrong as I thought it just records the pointer to windows or linux.
But now you made the concept clear. Now I am sure I will be able to dual boot windows 10 and Fedora 27 with this help.
Really appreciate your help.
Dr Nagalkar