grub rescue > : What do I do?

Post#1 by **francois** » 01 Apr 2025, 15:03

On my linux box while inspecting old usb keys for their contents, amongst which there were some old lubuntu install keys.

At some point rebooting my linux box, I was unable to boot. The error message is:

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grub rescue >

Detailed information to navigate into grub rescue mode
https://www.redswitches.com/blog/grub-rescue-commands/
https://unix.stackexchange.com/question ... -restoring

Specifically for asus:
https://www.asus.com/support/faq/1030210/

Essentially, the best way is to boot with an install key for a linux system,so they counsel.

I have used a lubuntu install key to boot my Asus laptop. Though I have indicated to my BIOS (using F1 at booting) to use my lubuntu install key, I keep getting the

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grub rescue >

as if the lubuntu install key does not boot. This usb key has been tested on one of my other linux boxes.

Any suggestion appreciated.

Thanks.

Post#2 by **francois** » 01 Apr 2025, 15:14

Additional information;
asus gaming thin and light laptop, 15.6-inch full hd , intel core i7-7700
https://icecat.biz/p/asus/90nr0gn1-m048 ... 89243.html

My other linux boxes, information necessary for ulterior work.
Toshiba sattelite z930, MSI-340-x, HP 1540ca. Toshiba will boot USB automatically without intervening in the bios. MSI to bios is F11 HP uses the F10 key.

Post#3 by **nanZor** » 03 Apr 2025, 01:53

Ah, an Asus ROG laptop. Ok. At this distance, and before going down the rabbithole of grub rescue I'd do these college tries:

1) Will it boot Porteus? Or perhaps PorteuX (2.0 is out now!)

2) Are you booting with any sdcards inserted? If so, remove and try again. I've had hardware change the internal enumeration on me with this before (like changing mmcblk0 to mmcblk1 depending on how it feels when starting!)

3) You indicated that this is an OLD key, and it doesn't appear it was *ever* successfully booted on the ROG. Have you tried the latest version of Lubuntu? Of course, I'd probably disable secure-boot, but perhaps this is why you are using a "signed" distro on that box?

4) Assuming you still have windows on it, have you ever done a restart? Restart and shutdown are slightly different, and on some boxes, I've had a RESTART stop the windows suspend/hibernation foolishness from hiding or properly operating the alternate boot-select / bypass keys.

Anyway, just some college tries that might narrow the scope before going full bananas with grub-rescue.

Post#4 by **francois** » 03 Apr 2025, 23:01

Hello nanZor!
1) It has been more than five years or a decade since I have tried to boot a linux box a porteus usb key. I will do. And I might try robang's installer:
Porteus USB live install
2) I have never booted from SD card with the ASUS, but I might try, I do it for raspbery pi.
3) Lubuntu key has been formated with latest OS edition, it works for my other linux box. In the ASUS BIOS priority was given to that specific usb key. I will look for the secure boot option.
4) I have windows on the ASUS. I will look into the procedure.

Thanks for your simple and efficient propositions.

Post#5 by **francois** » 07 Apr 2025, 01:49

Patience F2 and porteus bootable usb key.

It seems that a little patience was necessary.

I am now booting into the Asus. All there was to do was to boot once with the bootable usb key. Then booting with F2 and seting up booting order to address the bootable usb key allowed booting the linux box.

I did it with a porteus bootable system. Lubuntu usb bootable usb key does not provide an easy access to former files.

Backing up files on the partition.
The porteus usb key allowed me to backup the essential data on an external hdd. before reformating the system partition on which I will set a mixed porteus debian or ubuntu partition.

Restoring grub2 with update-grub using chroot from porteus
grub2 menu entry

I will take the occasion to install a more recent version of Debian.grub2 menu entry)

(to be followed).

Post#6 by **francois** » 08 Apr 2025, 00:44

It seems that I have reformated by error the first partition which was UEFI.

Post#7 by **francois** » 08 Apr 2025, 12:12

UEFI partitioning
https://wiki.archlinux.org/title/EFI_system_partition
https://askubuntu.com/questions/353683/ ... or-dummies

I have to understand what is needed to restore that partition and to populate it with the appropriate files to boot not only mbr for grub2 but also with windows 10.

Any cue to the procedure will be appreciated.

Thanks.

Post#8 by **Ed_P** » 08 Apr 2025, 16:47

francois wrote: ↑
08 Apr 2025, 12:12
what is needed to restore that partition and to populate it with the appropriate files to boot not only mbr for grub2 but also with windows 10.

FAT32, /EFI & /boot. If you put /porteus on the drive also no future work needed other than running the /boot/Porteus-installer. If you put /porteus on a different drive then the /boot/syslinux/porteus.cfg file must be edited to point to it before booting.

Post#9 by **francois** » 09 Apr 2025, 11:46

What I want to do is to restore the UEFI partition /dev/sda1 so that it is bootable both my windows 10 and grub linux.

I understand that you propose to format this UEFI partition FAT32

Then you propose that I put /EFI & /boot from the porteus iso into this /dev/sda1 partition.

I do not want to boot with syslinux but with grub2 to boot porteus.

Thanks.

Post#10 by **Ed_P** » 09 Apr 2025, 16:38

My grub2 USB boot menus:

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menuentry " Porteus 5.0 USB - EFI" --class slackware   --class user-icon-porteus  {

     set bootmgr=/EFI/boot/bootx64.efi         

     set bootdrv=$root
     search -f $bootmgr --set=root
     echo USB: $root
     sleep -v -i 4
     if [ $root != $bootdrv ]; then
        chainloader $bootmgr
     else
        echo "----------------------------------------"
        echo USB drive NOT found.
        echo
        sleep -v -i 10
     fi
     set root=$bootdrv
     }

menuentry " Porteus 5.0 USB - AF'" --class slackware   --class user-icon-porteus  {

     set bootparms="volume=33 reboot=cold extramod=/Modules"  #;cinnamon" # changes=EXIT:/changes/porteussave.dat"

     set bootdrv=$root
     search -f /boot/syslinux/vmlinuz --set=root
     if [ $root != $bootdrv ]; then
        linux  /boot/syslinux/vmlinuz $bootparms
        initrd /boot/syslinux/initrd.xz
     else
        echo "----------------------------------------"
        echo USB drive NOT found.
        echo
        sleep -v -i 10
     fi
     set root=$bootdrv
     }

Post#11 by **francois** » 15 Apr 2025, 13:54

@Ed:
As I have by error wiped my efi disk=/dev/sda1, I am very cautious not to do any additional wrong to my asus system.

fdisk -l gave me:

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Disk /dev/sda: 119.24 GiB, 128035676160 bytes, 250069680 sectors
Disk model: SanDisk SD8SNAT1
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disklabel type: gpt
Disk identifier: 5D36B5CE-9BF7-4994-9CAF-1218A3AE50E4

Device     Start       End   Sectors   Size Type
/dev/sda1   2048 250068991 250066944 119.2G Linux filesystem


Disk /dev/sdb: 931.51 GiB, 1000204886016 bytes, 1953525168 sectors
Disk model: TOSHIBA MQ01ABD1
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 4096 bytes
I/O size (minimum/optimal): 4096 bytes / 4096 bytes
Disklabel type: gpt
Disk identifier: B6E5572E-5DC7-4654-B768-D8441B05F958

Device         Start        End   Sectors   Size Type
/dev/sdb1       2048  976762879 976760832 465.8G Microsoft basic data
/dev/sdb2  976762880  977295359    532480   260M Microsoft basic data
/dev/sdb3  977295360 1953523875 976228516 465.5G Linux filesystem

Here are the contents of my hdd:

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root@porteus:/mnt/sdb2# cd /mnt/sdb1/
root@porteus:/mnt/sdb1# ls
$RECYCLE.BIN/          Oculus\ Apps/    System\ Volume\ Information/  WpSystem/
DeliveryOptimization/  Program\ Files/  WUDownloadCache/              fl/
InVirtuo/              SteamLibrary/    WindowsApps/                  vbox_virtual_disk/
root@porteus:/mnt/sdb1# cd /mnt/sdb2/
root@porteus:/mnt/sdb2# ls
$RECYCLE.BIN/  EFI/  System\ Volume\ Information/
root@porteus:/mnt/sdb2# cd /mnt/sdb3/
root@porteus:/mnt/sdb3# ls
00-grub-40custom/  boot/   etc/         isos/   lost+found/  opt/   run/   srv/      tmp/  vmlinuz@
50_porteus/        cdrom/  home/        lib/    media/       proc/  sbin/  swapfile  usr/
bin/               dev/    initrd.img@  lib64/  mnt/         root/  snap/  sys/      var/
root@porteus:/mnt/sdb3#

1) How can I reformat sda1 for EFI, so to recover the windows 10 intatallation and the linux installation (enabling grub2). I read that fat32 would be the option.
https://wiki.archlinux.org/title/EFI_system_partition

The UEFI specification mandates support for the FAT12, FAT16, and FAT32 file systems (see UEFI specification version 2.10, section 13.3.1.1), but any conformant vendor can optionally add support for additional file systems; for example, the firmware in Apple Macs supports the HFS+ file system.

To prevent potential issues with other operating systems and since the UEFI specification says that UEFI "encompasses the use of FAT32 for a system partition, and FAT12 or FAT16 for removable media"[5], it is recommended to use FAT32. Use the mkfs.fat(8) utility from dosfstools:

# mkfs.fat -F 32 /dev/sdxY

Is the EFI partition of your computer formatted FAT32? You have a computer hosting windows 10 or greater, I presume.

2) What folders do you have in your EFI partition?

Thanks.

Post#12 by **Ed_P** » 15 Apr 2025, 16:06

On my new Acer I have:

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root@porteus:/home/guest# fdisk -l
Disk /dev/loop0: 156.52 MiB, 164126720 bytes, 320560 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes


Disk /dev/loop1: 133.64 MiB, 140128256 bytes, 273688 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes


Disk /dev/loop2: 141.06 MiB, 147910656 bytes, 288888 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes


Disk /dev/loop3: 23.52 MiB, 24666112 bytes, 48176 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes


Disk /dev/loop4: 32.68 MiB, 34267136 bytes, 66928 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes


Disk /dev/loop5: 8 KiB, 8192 bytes, 16 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes


Disk /dev/loop6: 77.35 MiB, 81108992 bytes, 158416 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes


Disk /dev/loop7: 4 KiB, 4096 bytes, 8 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes


Disk /dev/loop8: 16 KiB, 16384 bytes, 32 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes


Disk /dev/loop9: 4 KiB, 4096 bytes, 8 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes


Disk /dev/loop10: 4 KiB, 4096 bytes, 8 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes


Disk /dev/loop11: 4.68 MiB, 4907008 bytes, 9584 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes


Disk /dev/nvme0n1: 953.87 GiB, 1024209543168 bytes, 2000409264 sectors
Disk model: WD PC SN740 SDDQNQD-1T00-1014           
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disklabel type: gpt
Disk identifier: 68887257-5E03-47ED-B413-0221072126C1

Device              Start        End   Sectors   Size Type
/dev/nvme0n1p1       2048     534527    532480   260M EFI System
/dev/nvme0n1p2     534528     567295     32768    16M Microsoft reserved
/dev/nvme0n1p3     567296  358967295 358400000 170.9G Microsoft basic data
/dev/nvme0n1p4 1998311424 2000408575   2097152     1G Windows recovery environme


Disk /dev/sda: 28.9 GiB, 31029460992 bytes, 60604416 sectors
Disk model: USB DISK 3.0    
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disklabel type: dos
Disk identifier: 0xe797b0fa

Device     Boot Start      End  Sectors  Size Id Type
/dev/sda1  *     8064 60604415 60596352 28.9G  c W95 FAT32 (LBA)
root@porteus:/home/guest#

sda is my Porteus USB drive. I don't have my ISOs here yet.

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guest@porteus:/mnt/nvme0n1p1$ ls -hon
total 8.0K
drwxrwxrwx 8 1000 4.0K Mar 30 12:32 EFI/
drwxrwxrwx 2 1000 4.0K Jun 12  2024 System\ Volume\ Information/
guest@porteus:/mnt/nvme0n1p1$ ls -hon EFI/
total 24K
drwxrwxrwx 2 1000 4.0K Jun 12  2024 Boot/
drwxrwxrwx 2 1000 4.0K Nov  1 06:46 Insyde/
drwxrwxrwx 4 1000 4.0K Mar 30 12:32 Microsoft/
drwxrwxrwx 4 1000 4.0K Jun 12  2024 OEM/
drwxrwxrwx 2 1000 4.0K Mar 28 14:32 UpdateCapsule/
drwxrwxrwx 3 1000 4.0K Apr 14 17:36 grub2win/
guest@porteus:/mnt/nvme0n1p1$

Added in 35 minutes 57 seconds:
On my Dell system:

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guest@porteus:/mnt/nvme0n1p1$ ls -hon 
total 4.0K
drwxrwxrwx 6 1000 2.0K Feb 25 12:51 EFI/
drwxrwxrwx 2 1000 2.0K Jul 12  2024 System\ Volume\ Information/
guest@porteus:/mnt/nvme0n1p1$ ls -hon EFI/
total 8.0K
drwxrwxrwx 2 1000 2.0K Jul 29  2021 Boot/
drwxrwxrwx 4 1000 2.0K Dec 10 17:49 Microsoft/
drwxrwxrwx 5 1000 2.0K Feb 25 12:51 dell/
drwxrwxrwx 3 1000 2.0K Nov 30 00:36 grub2win/
guest@porteus:/mnt/nvme0n1p1$ 
guest@porteus:/mnt/nvme0n1p1$ 

guest@porteus:/mnt/nvme0n1p1$ su
Password: 
root@porteus:/mnt/nvme0n1p1# fdisk -l
Disk /dev/loop0: 436.19 MiB, 457379840 bytes, 893320 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes


Disk /dev/loop1: 143.17 MiB, 150122496 bytes, 293208 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes


Disk /dev/loop2: 123.51 MiB, 129507328 bytes, 252944 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes


Disk /dev/loop3: 112.11 MiB, 117555200 bytes, 229600 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes


Disk /dev/loop4: 20.66 MiB, 21663744 bytes, 42312 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes


Disk /dev/loop5: 24.18 MiB, 25354240 bytes, 49520 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes


Disk /dev/loop6: 86.27 MiB, 90464256 bytes, 176688 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes


Disk /dev/loop7: 488 KiB, 499712 bytes, 976 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes


Disk /dev/loop8: 8 KiB, 8192 bytes, 16 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes


Disk /dev/loop9: 4 KiB, 4096 bytes, 8 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes


Disk /dev/loop10: 8 KiB, 8192 bytes, 16 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes


Disk /dev/loop11: 56 KiB, 57344 bytes, 112 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes


Disk /dev/loop12: 77.35 MiB, 81108992 bytes, 158416 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes


Disk /dev/loop13: 7.69 MiB, 8060928 bytes, 15744 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes


Disk /dev/loop14: 4 KiB, 4096 bytes, 8 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes


Disk /dev/loop15: 16 KiB, 16384 bytes, 32 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes


Disk /dev/loop16: 4 KiB, 4096 bytes, 8 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes


Disk /dev/nvme0n1: 931.51 GiB, 1000204886016 bytes, 1953525168 sectors
Disk model: WD Blue SN570 1TB                       
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disklabel type: gpt
Disk identifier: E55F6DA6-193F-4C16-9701-6B3AAFAACE8E

Device             Start        End   Sectors   Size Type
/dev/nvme0n1p1      2048     309247    307200   150M EFI System
/dev/nvme0n1p2    309248     571391    262144   128M Microsoft reserved
/dev/nvme0n1p3    571392  358971391 358400000 170.9G Microsoft basic data
/dev/nvme0n1p4 358971392  361519103   2547712   1.2G Windows recovery environment
/dev/nvme0n1p5 361519104  396333055  34813952  16.6G Windows recovery environment
/dev/nvme0n1p6 396333056  399190015   2856960   1.4G Windows recovery environment
/dev/nvme0n1p7 399190016  962932735 563742720 268.8G Microsoft basic data
/dev/nvme0n1p8 962932736 1953523711 990590976 472.4G Microsoft basic data
root@porteus:/mnt/nvme0n1p1#

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guest@porteus:/mnt/nvme0n1p1$ ls -hon EFI/Boot/
total 2.7M
-rwxrwxrwx 1 1000 2.7M Jan 15 00:45 bootx64.efi*
guest@porteus:/mnt/nvme0n1p1$

Post#13 by **francois** » 15 Apr 2025, 16:59

Another thread on UEFI:
https://superuser.com/questions/1708766 ... in-windows

Peculiar that you have such differences in the content of the UEFI partitions of your two different computers.

Thanks.

Post#14 by **Ed_P** » 15 Apr 2025, 18:31

The grub2win folder on each is my install of the Windows' Grub2Win app.

The Acer's EFI drive:

Code: Select all

guest@porteus:/mnt/nvme0n1p1$ ls -hon EFI/
total 24K
drwxrwxrwx 2 1000 4.0K Jun 12  2024 Boot/
drwxrwxrwx 2 1000 4.0K Nov  1 06:46 Insyde/
drwxrwxrwx 4 1000 4.0K Mar 30 12:32 Microsoft/
drwxrwxrwx 4 1000 4.0K Jun 12  2024 OEM/
drwxrwxrwx 2 1000 4.0K Mar 28 14:32 UpdateCapsule/
drwxrwxrwx 3 1000 4.0K Apr 14 17:36 grub2win/
guest@porteus:/mnt/nvme0n1p1$ ls -hon EFI/Boot/
total 2.7M
-rwxrwxrwx 1 1000 2.7M Mar 30 10:58 bootx64.efi*
guest@porteus:/mnt/nvme0n1p1$ ls -hon EFI/Microsoft/
total 12K
drwxrwxrwx 42 1000 8.0K Mar 30 12:32 Boot/
drwxrwxrwx  2 1000 4.0K Jun 12  2024 Recovery/
guest@porteus:/mnt/nvme0n1p1$ ls -hon EFI/Microsoft/Boot/
total 11M
-rwxrwxrwx 1 1000  52K Apr 15 14:19 BCD*
-rwxrwxrwx 1 1000  64K Jun 12  2024 BCD.LOG*
-rwxrwxrwx 1 1000    0 Jun 12  2024 BCD.LOG1*
-rwxrwxrwx 1 1000    0 Jun 12  2024 BCD.LOG2*
-rwxrwxrwx 1 1000  64K Apr  8 22:32 BOOTSTAT.DAT*
drwxrwxrwx 3 1000 4.0K Jun 12  2024 CIPolicies/
drwxrwxrwx 2 1000 4.0K Jun 12  2024 Fonts/
drwxrwxrwx 3 1000 4.0K Jun 12  2024 Resources/
-rwxrwxrwx 1 1000 159K Mar 30 10:58 SecureBootRecovery.efi*
drwxrwxrwx 2 1000 4.0K Jun 12  2024 bg-BG/
-rwxrwxrwx 1 1000  11K Apr  1  2024 boot.stl*
-rwxrwxrwx 1 1000 2.7M Mar 30 10:58 bootmgfw.efi*
-rwxrwxrwx 1 1000 2.7M Mar 30 10:58 bootmgr.efi*
drwxrwxrwx 2 1000 4.0K Jun 12  2024 cs-CZ/
drwxrwxrwx 2 1000 4.0K Jun 12  2024 da-DK/
drwxrwxrwx 2 1000 4.0K Jun 12  2024 de-DE/
drwxrwxrwx 2 1000 4.0K Jun 12  2024 el-GR/
drwxrwxrwx 2 1000 4.0K Jun 12  2024 en-GB/
drwxrwxrwx 2 1000 4.0K Jun 12  2024 en-US/
drwxrwxrwx 2 1000 4.0K Jun 12  2024 es-ES/
drwxrwxrwx 2 1000 4.0K Jun 12  2024 es-MX/
drwxrwxrwx 2 1000 4.0K Jun 12  2024 et-EE/
drwxrwxrwx 2 1000 4.0K Jun 12  2024 fi-FI/
drwxrwxrwx 2 1000 4.0K Jun 12  2024 fr-CA/
drwxrwxrwx 2 1000 4.0K Jun 12  2024 fr-FR/
drwxrwxrwx 2 1000 4.0K Jun 12  2024 hr-HR/
drwxrwxrwx 2 1000 4.0K Jun 12  2024 hu-HU/
drwxrwxrwx 2 1000 4.0K Jun 12  2024 it-IT/
drwxrwxrwx 2 1000 4.0K Jun 12  2024 ja-JP/
-rwxrwxrwx 1 1000  70K Mar 30 10:58 kd_02_10df.dll*
-rwxrwxrwx 1 1000 466K Mar 30 10:57 kd_02_10ec.dll*
-rwxrwxrwx 1 1000  70K Mar 30 10:58 kd_02_1137.dll*
-rwxrwxrwx 1 1000  98K Mar 30 10:58 kd_02_1414.dll*
-rwxrwxrwx 1 1000 278K Mar 30 10:58 kd_02_14e4.dll*
-rwxrwxrwx 1 1000  58K Mar 30 10:58 kd_02_15ad.dll*
-rwxrwxrwx 1 1000  90K Mar 30 10:58 kd_02_15b3.dll*
-rwxrwxrwx 1 1000  82K Mar 30 10:58 kd_02_1969.dll*
-rwxrwxrwx 1 1000  70K Mar 30 10:58 kd_02_19a2.dll*
-rwxrwxrwx 1 1000  62K Mar 30 10:58 kd_02_1af4.dll*
-rwxrwxrwx 1 1000 354K Mar 30 10:58 kd_02_8086.dll*
-rwxrwxrwx 1 1000  58K Mar 30 10:58 kd_07_1415.dll*
-rwxrwxrwx 1 1000  86K Mar 30 10:58 kd_0C_8086.dll*
-rwxrwxrwx 1 1000  58K Mar 30 10:58 kdnet_uart16550.dll*
-rwxrwxrwx 1 1000  86K Mar 30 10:58 kdstub.dll*
drwxrwxrwx 2 1000 4.0K Jun 12  2024 ko-KR/
drwxrwxrwx 2 1000 4.0K Jun 12  2024 lt-LT/
drwxrwxrwx 2 1000 4.0K Jun 12  2024 lv-LV/
-rwxrwxrwx 1 1000 2.5M Apr  8 16:52 memtest.efi*
drwxrwxrwx 2 1000 4.0K Jun 12  2024 nb-NO/
drwxrwxrwx 2 1000 4.0K Jun 12  2024 nl-NL/
drwxrwxrwx 2 1000 4.0K Jun 12  2024 pl-PL/
drwxrwxrwx 2 1000 4.0K Jun 12  2024 pt-BR/
drwxrwxrwx 2 1000 4.0K Jun 12  2024 pt-PT/
drwxrwxrwx 2 1000 4.0K Jun 12  2024 qps-ploc/
drwxrwxrwx 2 1000 4.0K Mar 30 12:29 qps-plocm/
drwxrwxrwx 2 1000 4.0K Jun 12  2024 ro-RO/
drwxrwxrwx 2 1000 4.0K Jun 12  2024 ru-RU/
drwxrwxrwx 2 1000 4.0K Jun 12  2024 sk-SK/
drwxrwxrwx 2 1000 4.0K Jun 12  2024 sl-SI/
drwxrwxrwx 2 1000 4.0K Jun 12  2024 sr-Latn-RS/
drwxrwxrwx 2 1000 4.0K Jun 12  2024 sv-SE/
drwxrwxrwx 2 1000 4.0K Jun 12  2024 tr-TR/
drwxrwxrwx 2 1000 4.0K Jun 12  2024 uk-UA/
-rwxrwxrwx 1 1000  11K Apr  1  2024 winsipolicy.p7b*
drwxrwxrwx 2 1000 4.0K Jun 12  2024 zh-CN/
drwxrwxrwx 2 1000 4.0K Jun 12  2024 zh-TW/
guest@porteus:/mnt/nvme0n1p1$ ls -hon EFI/grub2win
total 4.0K
drwxrwxrwx 2 1000 4.0K Apr 14 17:36 g2bootmgr/
guest@porteus:/mnt/nvme0n1p1$ ls -hon EFI/grub2win/g2bootmgr/
total 1.9M
-rwxrwxrwx 1 1000 5.8K Mar  9  2024 gnugrub.bootinfo.cfg*
-rwxrwxrwx 1 1000  16K Dec 24  2022 gnugrub.diskutil.cfg*
-rwxrwxrwx 1 1000   23 Apr 14 17:36 gnugrub.efipart.settings.txt*
-rwxrwxrwx 1 1000 4.4K Nov 24  2022 gnugrub.efirescue.cfg*
-rwxrwxrwx 1 1000 3.0K Dec 11  2023 gnugrub.efisetup.cfg*
-rwxrwxrwx 1 1000  14K Feb 25  2024 gnugrub.functions.cfg*
-rwxrwxrwx 1 1000  46K Feb 11  2024 gnugrub.kernel.bios*
-rwxrwxrwx 1 1000 408K Feb 11  2024 gnugrub.kernel32.efi*
-rwxrwxrwx 1 1000 736K Feb  7 18:44 gnugrub.kernel64.efi*
-rwxrwxrwx 1 1000 9.5K Aug  1  2024 gnugrub.videoutil.cfg*
-rwxrwxrwx 1 1000 407K Feb 19  2024 microsoft.bootmgr.bios*
-rwxrwxrwx 1 1000 245K May 15  2008 microsoft.ntldr.xp.bios*
guest@porteus:/mnt/nvme0n1p1$

The other EFI folders are vendor related to harddrive recovery imo.

And yes, all EFI folders are on FAT32 formatted drives. An EFI requirement.

Post#15 by **francois** » 18 Apr 2025, 17:37

By error I erased my /mnt/sda1 EFI partition.

On /mnt/sdb2 there is the windows file system and on /mnt/sdb3 there was my kubuntu and porteus filesystem. I would like to recover the windows 10 partitions information. All my other data is backed up on an external hdd.

I was unable to boot. The error message being:
grub rescue >

Grub rescue commands would not restore the bootloader.

Using a kubuntu 24.04.2 LTS live iso, I was able to reformat /mnt/sda1 to fat32. Within the new EFI partion, I have installed some EFI files.

![EFI-content|562x123](upload://wJTPxJ00PLJhtvtWYUD94YNJg5R.png)

I have tried different approaches.

The last one being restoring uefi partition, grub bootloader and windows 10 bootloder with windows 10 iso thru a linux system.
Now I am going with the windows 10 iso, for the free iso:
(https://www.microsoft.com/en-ca/softwar ... ndows10ISO)

The procedure under ubuntu to prepare the windows 10 iso (you cannot format to usb with dd):
[https://www.linuxbabe.com/ubuntu/easily ... usb-ubuntu](https://www.linuxbabe.com/ubuntu/easily ... usb-ubuntu)

Once the windows boot usb key is ready, it should boot your dual boot linux box:
[https://www.linuxbabe.com/ubuntu/easily ... usb-ubuntu](https://www.linuxbabe.com/ubuntu/easily ... usb-ubuntu)
<em>boot it from this USB stick and install Windows 10 in UEFI mode. Keep in mind that you may need to disable compatibility support module (CSM) in the firmware in order to boot in UEFI mode. You may also need to remove USB stick from your computer and insert it back in order for the firmware to detect the boot loader on your USB stick.</em>

Unlike the kubuntu usb live system, the Windows 10 key will not boot.

Any suggestion appreciated.

Thanks.