You are not logged in.

#1 2021-01-13 12:42:23

DigitalCyan
Member
Registered: 2021-01-13
Posts: 10

[SOLVED] os-prober failing to locate Windows 10 after Arch reinstall

What I did:
My system has 3 drives, 1st one is an M.2 that has grub on it and arch, the second one is Windows and the 3rd one is just for storage. I had some issues with Arch so I reinstalled it last night, today I wanted to do the usual os-prober followed by grub-mkconfig to get my windows back and running but os-prober doesn't seem to find it. I am running UEFI.

How did I try to resolve the issue:
I used os-prober to try to get Windows as I usually do, I also made sure i have ntfs-3g installed and drives mounted (via thunar's gvfs) but that didn't budge.

lsblk output:

NAME        MAJ:MIN RM   SIZE RO TYPE MOUNTPOINT
sda           8:0    0 223.6G  0 disk 
|-sda1        8:1    0    16M  0 part 
`-sda2        8:2    0 223.6G  0 part /run/media/username/9A28FCC028FC9D07
sdb           8:16   0 931.5G  0 disk 
|-sdb1        8:17   0    16M  0 part 
`-sdb2        8:18   0 931.5G  0 part /run/media/username/067600AA76009D15
sr0          11:0    1  1024M  0 rom  
nvme0n1     259:0    0 238.5G  0 disk 
|-nvme0n1p1 259:1    0   512M  0 part /boot
|-nvme0n1p2 259:2    0     2G  0 part [SWAP]
`-nvme0n1p3 259:3    0   236G  0 part /

My grub.cfg:

#
# DO NOT EDIT THIS FILE
#
# It is automatically generated by grub-mkconfig using templates
# from /etc/grub.d and settings from /etc/default/grub
#

### BEGIN /etc/grub.d/00_header ###
insmod part_gpt
insmod part_msdos
if [ -s $prefix/grubenv ]; then
  load_env
fi
if [ "${next_entry}" ] ; then
   set default="${next_entry}"
   set next_entry=
   save_env next_entry
   set boot_once=true
else
   set default="0"
fi

if [ x"${feature_menuentry_id}" = xy ]; then
  menuentry_id_option="--id"
else
  menuentry_id_option=""
fi

export menuentry_id_option

if [ "${prev_saved_entry}" ]; then
  set saved_entry="${prev_saved_entry}"
  save_env saved_entry
  set prev_saved_entry=
  save_env prev_saved_entry
  set boot_once=true
fi

function savedefault {
  if [ -z "${boot_once}" ]; then
    saved_entry="${chosen}"
    save_env saved_entry
  fi
}

function load_video {
  if [ x$feature_all_video_module = xy ]; then
    insmod all_video
  else
    insmod efi_gop
    insmod efi_uga
    insmod ieee1275_fb
    insmod vbe
    insmod vga
    insmod video_bochs
    insmod video_cirrus
  fi
}

if [ x$feature_default_font_path = xy ] ; then
   font=unicode
else
insmod part_gpt
insmod ext2
if [ x$feature_platform_search_hint = xy ]; then
  search --no-floppy --fs-uuid --set=root  8990e5bd-f33c-45cc-80df-96e0dc3f7537
else
  search --no-floppy --fs-uuid --set=root 8990e5bd-f33c-45cc-80df-96e0dc3f7537
fi
    font="/usr/share/grub/unicode.pf2"
fi

if loadfont $font ; then
  set gfxmode=auto
  load_video
  insmod gfxterm
fi
terminal_input console
terminal_output gfxterm
if [ x$feature_timeout_style = xy ] ; then
  set timeout_style=menu
  set timeout=5
# Fallback normal timeout code in case the timeout_style feature is
# unavailable.
else
  set timeout=5
fi
### END /etc/grub.d/00_header ###

### BEGIN /etc/grub.d/10_linux ###
menuentry 'Arch Linux' --class arch --class gnu-linux --class gnu --class os $menuentry_id_option 'gnulinux-simple-8990e5bd-f33c-45cc-80df-96e0dc3f7537' {
	load_video
	set gfxpayload=keep
	insmod gzio
	insmod part_gpt
	insmod fat
	if [ x$feature_platform_search_hint = xy ]; then
	  search --no-floppy --fs-uuid --set=root  6DFC-3A6B
	else
	  search --no-floppy --fs-uuid --set=root 6DFC-3A6B
	fi
	echo	'Loading Linux linux ...'
	linux	/vmlinuz-linux root=UUID=8990e5bd-f33c-45cc-80df-96e0dc3f7537 rw  loglevel=3 quiet
	echo	'Loading initial ramdisk ...'
	initrd	/initramfs-linux.img
}
submenu 'Advanced options for Arch Linux' $menuentry_id_option 'gnulinux-advanced-8990e5bd-f33c-45cc-80df-96e0dc3f7537' {
	menuentry 'Arch Linux, with Linux linux' --class arch --class gnu-linux --class gnu --class os $menuentry_id_option 'gnulinux-linux-advanced-8990e5bd-f33c-45cc-80df-96e0dc3f7537' {
		load_video
		set gfxpayload=keep
		insmod gzio
		insmod part_gpt
		insmod fat
		if [ x$feature_platform_search_hint = xy ]; then
		  search --no-floppy --fs-uuid --set=root  6DFC-3A6B
		else
		  search --no-floppy --fs-uuid --set=root 6DFC-3A6B
		fi
		echo	'Loading Linux linux ...'
		linux	/vmlinuz-linux root=UUID=8990e5bd-f33c-45cc-80df-96e0dc3f7537 rw  loglevel=3 quiet
		echo	'Loading initial ramdisk ...'
		initrd	/initramfs-linux.img
	}
	menuentry 'Arch Linux, with Linux linux (fallback initramfs)' --class arch --class gnu-linux --class gnu --class os $menuentry_id_option 'gnulinux-linux-fallback-8990e5bd-f33c-45cc-80df-96e0dc3f7537' {
		load_video
		set gfxpayload=keep
		insmod gzio
		insmod part_gpt
		insmod fat
		if [ x$feature_platform_search_hint = xy ]; then
		  search --no-floppy --fs-uuid --set=root  6DFC-3A6B
		else
		  search --no-floppy --fs-uuid --set=root 6DFC-3A6B
		fi
		echo	'Loading Linux linux ...'
		linux	/vmlinuz-linux root=UUID=8990e5bd-f33c-45cc-80df-96e0dc3f7537 rw  loglevel=3 quiet
		echo	'Loading initial ramdisk ...'
		initrd	/initramfs-linux-fallback.img
	}
}

### END /etc/grub.d/10_linux ###

### BEGIN /etc/grub.d/20_linux_xen ###
### END /etc/grub.d/20_linux_xen ###

### BEGIN /etc/grub.d/30_os-prober ###
### END /etc/grub.d/30_os-prober ###

### BEGIN /etc/grub.d/40_custom ###
# This file provides an easy way to add custom menu entries.  Simply type the
# menu entries you want to add after this comment.  Be careful not to change
# the 'exec tail' line above.
### END /etc/grub.d/40_custom ###

### BEGIN /etc/grub.d/41_custom ###
if [ -f  ${config_directory}/custom.cfg ]; then
  source ${config_directory}/custom.cfg
elif [ -z "${config_directory}" -a -f  $prefix/custom.cfg ]; then
  source $prefix/custom.cfg;
fi
### END /etc/grub.d/41_custom ###

Now I am unsure what grub exactly does when it installs itself but last time I had a similar issue my Windows Boot Manager somehow found itself on my M.2 (where I keep grub and arch).

EDIT: I am also event less sure if allowing windows to fix itself via the installation medium will brick grub so I'm still holding my fire on that one.

Last edited by DigitalCyan (2021-01-17 23:25:26)

Offline

#2 2021-01-13 12:49:09

kocotian
Member
From: Łaguszów, Poland
Registered: 2020-07-24
Posts: 40
Website

Re: [SOLVED] os-prober failing to locate Windows 10 after Arch reinstall

Are you sure that Windows's NTFS partition was clearly unmounted (not hibernated, which is often even if you "Power Off" windows)? Usually you will get information about it when you try to mount NTFS partition.
If yes, try to mount with hibernation file removal (as root):

mount -t ntfs-3g -o remove_hiberfile /dev/<NTFS> <MOUNTPOINT>

and try again.

Offline

#3 2021-01-13 13:08:48

DigitalCyan
Member
Registered: 2021-01-13
Posts: 10

Re: [SOLVED] os-prober failing to locate Windows 10 after Arch reinstall

Alright so ive tried what you said and this is what I've got.

sudo mount -t ntfs-3g -o remove_hiberfile /dev/sda1 /mnt/win
NTFS signature is missing.
Failed to mount '/dev/sda1': Invalid argument
The device '/dev/sda1' doesn't seem to have a valid NTFS.
Maybe the wrong device is used? Or the whole disk instead of a
partition (e.g. /dev/sda, not /dev/sda1)? Or the other way around?

So after being questioned about my partition choices, i did:

sudo mount -t ntfs-3g -o remove_hiberfile /dev/sda /mnt/win 
NTFS signature is missing.
Failed to mount '/dev/sda': Invalid argument
The device '/dev/sda' doesn't seem to have a valid NTFS.
Maybe the wrong device is used? Or the whole disk instead of a
partition (e.g. /dev/sda, not /dev/sda1)? Or the other way around?

EDIT:
Also I made sure the drive didnt actually get mounted

lsblk
NAME        MAJ:MIN RM   SIZE RO TYPE MOUNTPOINT
sda           8:0    0 223.6G  0 disk 
|-sda1        8:1    0    16M  0 part 
`-sda2        8:2    0 223.6G  0 part 
sdb           8:16   0 931.5G  0 disk 
|-sdb1        8:17   0    16M  0 part 
`-sdb2        8:18   0 931.5G  0 part 
sr0          11:0    1  1024M  0 rom  
nvme0n1     259:0    0 238.5G  0 disk 
|-nvme0n1p1 259:1    0   512M  0 part /boot
|-nvme0n1p2 259:2    0     2G  0 part [SWAP]
`-nvme0n1p3 259:3    0   236G  0 part /

Also, quick note, using Thunar I was able to browse my NTFS filesystems.

Last edited by DigitalCyan (2021-01-13 13:13:21)

Offline

#4 2021-01-13 13:40:43

seth
Member
Registered: 2012-09-03
Posts: 49,967

Re: [SOLVED] os-prober failing to locate Windows 10 after Arch reinstall

lsblk -f

The windows bootloader might be on one of the 16M partitions.

Offline

#5 2021-01-13 13:44:08

DigitalCyan
Member
Registered: 2021-01-13
Posts: 10

Re: [SOLVED] os-prober failing to locate Windows 10 after Arch reinstall

Perhaps... here's lsblk -f:

lsblk -f
NAME        FSTYPE FSVER LABEL UUID                                 FSAVAIL FSUSE% MOUNTPOINT
sda                                                                                
|-sda1                                                                             
`-sda2      ntfs               9A28FCC028FC9D07                                    
sdb                                                                                
|-sdb1                                                                             
`-sdb2      ntfs               067600AA76009D15                                    
sr0                                                                                
nvme0n1                                                                            
|-nvme0n1p1 vfat   FAT32       6DFC-3A6B                             454.1M    11% /boot
|-nvme0n1p2 swap   1           9f3bd583-66a4-4a93-9023-0250d5ab5db6                [SWAP]
`-nvme0n1p3 ext4   1.0         8990e5bd-f33c-45cc-80df-96e0dc3f7537  210.8G     4% /

Offline

#6 2021-01-13 19:37:52

seth
Member
Registered: 2012-09-03
Posts: 49,967

Re: [SOLVED] os-prober failing to locate Windows 10 after Arch reinstall

The tow ntfs partitions are sda2 and sdb2, god knows what those 16MB partitions are.
Mount them and check whether either contains an "EFI" directory

Offline

#7 2021-01-13 22:11:43

GeorgeJP
Member
From: Czech Republic
Registered: 2020-01-28
Posts: 185

Re: [SOLVED] os-prober failing to locate Windows 10 after Arch reinstall

seth wrote:

The tow ntfs partitions are sda2 and sdb2, god knows what those 16MB partitions are.
Mount them and check whether either contains an "EFI" directory

16MB partitions are 'Microsoft reserved partitions' without any filesystem.
Windows need them for some raw disk operations.
In Linux they should be ignored (not mounted/used)

Offline

#8 2021-01-14 00:09:42

DigitalCyan
Member
Registered: 2021-01-13
Posts: 10

Re: [SOLVED] os-prober failing to locate Windows 10 after Arch reinstall

Ok so I mounted both partitions like this and checked their contents

NAME FSTYPE FSVER LABEL UUID                                 FSAVAIL FSUSE% MOUNTPOINT
sda                                                                         
|-sda1
|                                                                           
`-sda2
     ntfs               9A28FCC028FC9D07                        112G    50% /mnt/win/a
sdb                                                                         
|-sdb1
|                                                                           
`-sdb2
     ntfs               067600AA76009D15                      751.3G    19% /mnt/win/b
sr0                                                                         
nvme0n1
|                                                                           
|-nvme0n1p1
|    vfat   FAT32       6DFC-3A6B                             454.1M    11% /boot
|-nvme0n1p2
|    swap   1           9f3bd583-66a4-4a93-9023-0250d5ab5db6                [SWAP]
`-nvme0n1p3
     ext4   1.0         8990e5bd-f33c-45cc-80df-96e0dc3f7537  208.2G     5% /

sda2 is my used-to-be C:\ with your classic Windows layout, It does have some folders I didn't notice before tho such as bootmgr, BOOTNXT, swapfile.sys, hiberfil.sys and pagefile.sys.
sdb2 is just my 1TB main storage, nothing out of order there.

Offline

#9 2021-01-14 00:17:45

GeorgeJP
Member
From: Czech Republic
Registered: 2020-01-28
Posts: 185

Re: [SOLVED] os-prober failing to locate Windows 10 after Arch reinstall

How did you reinstall arch?
Did you reformat efi partition (nvme0n1p1) accidentally?
Check if your /boot folder contains Windows boot files.

DigitalCyan wrote:

my Windows Boot Manager somehow found itself on my M.2 (where I keep grub and arch).

That is correct. EFI partition must contain boot files for both arch and windows.
If windows files are missing, you should repair windows boot, this will break grub and then repair arch boot.

Last edited by GeorgeJP (2021-01-14 00:35:42)

Offline

#10 2021-01-14 00:49:44

DigitalCyan
Member
Registered: 2021-01-13
Posts: 10

Re: [SOLVED] os-prober failing to locate Windows 10 after Arch reinstall

GeorgeJP wrote:

How did you reinstall arch?
Did you reformat efi partition (nvme0n1p1) accidentally?
Check if your /boot folder contains Windows boot files.

DigitalCyan wrote:

my Windows Boot Manager somehow found itself on my M.2 (where I keep grub and arch).

That is correct. EFI partition must contain boot files for both arch and windows.
If windows files are missing, you should repair windows boot, this will break grub and then repair arch boot.

That probably is what happened.

So I first installed Arch, then Win, then Arch. So if i get it right. My windows bootloader got moved from my sda1 to nvme0n1p1 since i installed grub over to the grub's partition, correct?

So by fixing windows via repair tool I am bound to break grub.

Offline

#11 2021-01-14 00:58:42

loqs
Member
Registered: 2014-03-06
Posts: 17,192

Re: [SOLVED] os-prober failing to locate Windows 10 after Arch reinstall

DigitalCyan wrote:

So I first installed Arch, then Win, then Arch. So if i get it right. My windows bootloader got moved from my sda1 to nvme0n1p1 since i installed grub over to the grub's partition, correct?

Installing grub would not move any files belonging to a different OS from one filesystem to another.

Offline

#12 2021-01-14 01:09:41

GeorgeJP
Member
From: Czech Republic
Registered: 2020-01-28
Posts: 185

Re: [SOLVED] os-prober failing to locate Windows 10 after Arch reinstall

DigitalCyan wrote:

So I first installed Arch, then Win, then Arch. So if i get it right. My windows bootloader got moved from my sda1 to nvme0n1p1 since i installed grub over to the grub's partition, correct

Not correct.
If you first installed Arch, then during this installation EFI partition was created.
When you install Windows, it install his boot files also to this EFI partition.
If you reinstall Arch, you should not touch windows files on EFI partition.

DigitalCyan wrote:

So by fixing windows via repair tool I am bound to break grub.

Yes, Windows is not friendly to other OS and expects to be alone in PC.
https://wiki.archlinux.org/index.php/Du … th_Windows

Offline

#13 2021-01-14 03:23:21

DigitalCyan
Member
Registered: 2021-01-13
Posts: 10

Re: [SOLVED] os-prober failing to locate Windows 10 after Arch reinstall

Thanks for the info, but before I mark the thread solved, something is still grinding my gears...

GeorgeJP wrote:

When you install Windows, it install his boot files also to this EFI partition.

In my specific case I installed Arch on drive no. 1, then installed Win on drive no. 2. Why would windows overwrite a partition that is on an another drive?

Can't there be multiple EFI partitions? Shouldn't installing each OS on it's own drive give it it's own environment to work with?

Offline

#14 2021-01-14 03:34:36

loqs
Member
Registered: 2014-03-06
Posts: 17,192

Re: [SOLVED] os-prober failing to locate Windows 10 after Arch reinstall

There can be multiple ESP's.  The firmware does not treat them as separate and may not even properly support such a configuration.
Why would WIndows need to overwrite the existing ESP it located to add its own files and set itself as the default entry?

Offline

#15 2021-01-14 04:43:15

DigitalCyan
Member
Registered: 2021-01-13
Posts: 10

Re: [SOLVED] os-prober failing to locate Windows 10 after Arch reinstall

loqs wrote:

There can be multiple ESP's.  The firmware does not treat them as separate and may not even properly support such a configuration.
Why would WIndows need to overwrite the existing ESP it located to add its own files and set itself as the default entry?

See that is the part I do not get.

I install Arch and theres an ESP partition on /nvme0n1p1
I install Windows and an ESP partition gets created on /sda1
I add Windows to grub (by using os-prober and grub-mkconfig)
I reinstall Arch again on the same drive and I make the ESP sit under /nvme0n1p1
I loose access to Windows

Last time I had the same issue I saw that Windows Boot Manager was sitting on /nvme0n1p1 for some reason.
I doubt it's a mistake cause everything else windows related like program files and stuff was on /sda2 (implying that /sda1 is the small managment partition created by Win we discussed earlier)

I don't get it, but no matter, will probably reinstall Win from scratch tommorow and add it to grub again, I will post my findings here so I'll keep the thread open for a little longer for the sake of documenting this issue.

Offline

#16 2021-01-14 05:31:59

loqs
Member
Registered: 2014-03-06
Posts: 17,192

Re: [SOLVED] os-prober failing to locate Windows 10 after Arch reinstall

Please post the output of `parted -l`
Edit:

DigitalCyan wrote:

I install Arch and theres an ESP partition on /nvme0n1p1
I install Windows and an ESP partition gets created on /sda1

I believe you are mistaken here.  16M matches the size used for the Microsoft Reserved Partition.  From Microsoft's own documentation the minimum size Windows requires for an ESP is 100M [1] and to accommodate 4KN drives defaults to 260M.

DigitalCyan wrote:

I add Windows to grub (by using os-prober and grub-mkconfig)
I reinstall Arch again on the same drive and I make the ESP sit under /nvme0n1p1
I loose access to Windows

If you formatted the ESP that Windows was sharing with Arch removing Windows boot mechanism that would explain loss of access to Windows.

[1] https://docs.microsoft.com/en-us/window … partitions

Last edited by loqs (2021-01-14 05:59:39)

Offline

#17 2021-01-14 09:01:35

GeorgeJP
Member
From: Czech Republic
Registered: 2020-01-28
Posts: 185

Re: [SOLVED] os-prober failing to locate Windows 10 after Arch reinstall

loqs wrote:

There can be multiple ESP's.  The firmware does not treat them as separate and may not even properly support such a configuration.
Why would WIndows need to overwrite the existing ESP it located to add its own files and set itself as the default entry?

Usually there can be one ESP per drive.
Windows just adds his files to ESP and set itself as default in UEFI NVRAM.
OP have 3 disks, only nvme is bootable (have ESP partition), used by both OS.
|-nvme0n1p1
|    vfat   FAT32       6DFC-3A6B                             454.1M    11% /boot
Ocuppied size 11% of 454MB leds me to assumption, that during second Arch install this partition was formatted and win boot entries wiped and only grub is present.

DigitalCyan wrote:

I install Arch and theres an ESP partition on /nvme0n1p1
I install Windows and an ESP partition gets created on /sda1

Windows installation was not creating ESP on /sda1. ESP created by Arch on /nvme0n1p1 was used.

Offline

#18 2021-01-15 02:19:51

DigitalCyan
Member
Registered: 2021-01-13
Posts: 10

Re: [SOLVED] os-prober failing to locate Windows 10 after Arch reinstall

GeorgeJP wrote:

OP have 3 disks, only nvme is bootable (have ESP partition), used by both OS.

Yes but there should be 2 bootable disks if i installed Arch on one disk and Windows on the other.

loqs wrote:

Please post the output of `parted -l`

Here you go bud.

Model: ATA WDC WDS240G2G0A- (scsi)
Disk /dev/sda: 240GB
Sector size (logical/physical): 512B/512B
Partition Table: gpt
Disk Flags: 

Number  Start   End     Size    File system  Name                          Flags
 1      1049kB  17.8MB  16.8MB               Microsoft reserved partition  msftres
 2      17.8MB  240GB   240GB   ntfs         Basic data partition          msftdata


Model: ATA ST1000DM003-1ER1 (scsi)
Disk /dev/sdb: 1000GB
Sector size (logical/physical): 512B/4096B
Partition Table: gpt
Disk Flags: 

Number  Start   End     Size    File system  Name                          Flags
 1      1049kB  17.8MB  16.8MB               Microsoft reserved partition  msftres
 2      17.8MB  1000GB  1000GB  ntfs         Basic data partition          msftdata


Model: ADATA SX8200PNP (nvme)
Disk /dev/nvme0n1: 256GB
Sector size (logical/physical): 512B/512B
Partition Table: gpt
Disk Flags: 

Number  Start   End     Size    File system     Name  Flags
 1      1049kB  538MB   537MB   fat32                 boot, esp
 2      538MB   2685MB  2147MB  linux-swap(v1)        swap
 3      2685MB  256GB   253GB   ext4

Offline

#19 2021-01-15 02:55:27

loqs
Member
Registered: 2014-03-06
Posts: 17,192

Re: [SOLVED] os-prober failing to locate Windows 10 after Arch reinstall

 1      1049kB  538MB   537MB   fat32                 boot, esp

The only ESP in the output.  DigitalCyan please read my edit to post 16.  You continue to contend Windows created an ESP on sda without explaining how you determined that or providing an explanation for why it is no longer present.

Offline

#20 2021-01-15 11:17:17

GeorgeJP
Member
From: Czech Republic
Registered: 2020-01-28
Posts: 185

Re: [SOLVED] os-prober failing to locate Windows 10 after Arch reinstall

DigitalCyan wrote:

Yes but there should be 2 bootable disks if i installed Arch on one disk and Windows on the other.

NO. There is only one ESP. Only one boot disk.

Please post output

tree /boot

To be able boot window you should have something similiar available on ESP partition (shortened)

/boot
├── EFI
│   ├── Microsoft
│   │   ├── Boot
│   │   │   ├── BCD
│   │   │   ├── BCD.LOG
│   │   │   ├── BCD.LOG1
│   │   │   ├── BCD.LOG2
│   │   │   ├── bootmgfw.efi
│   │   │   ├── bootmgr.efi
│   │   │   ├── BOOTSTAT.DAT
│   │   │   ├── boot.stl
│   │   │   ├── en-US
│   │   │   │   ├── bootmgfw.efi.mui
│   │   │   │   ├── bootmgr.efi.mui
│   │   │   │   └── memtest.efi.mui
│   │   │   ├── Fonts
│   │   │   │   ├── chs_boot.ttf
│   │   │   │   ├── cht_boot.ttf
│   │   │   │   ├── jpn_boot.ttf
│   │   │   │   ├── kor_boot.ttf
│   │   │   │   ├── malgun_boot.ttf
│   │   │   │   ├── malgunn_boot.ttf
│   │   │   │   ├── meiryo_boot.ttf
│   │   │   │   ├── meiryon_boot.ttf
│   │   │   │   ├── msjh_boot.ttf
│   │   │   │   ├── msjhn_boot.ttf
│   │   │   │   ├── msyh_boot.ttf
│   │   │   │   ├── msyhn_boot.ttf
│   │   │   │   ├── segmono_boot.ttf
│   │   │   │   ├── segoen_slboot.ttf
│   │   │   │   ├── segoe_slboot.ttf
│   │   │   │   └── wgl4_boot.ttf
│   │   │   ├── kdstub.dll
│   │   │   ├── kd_0C_8086.dll
│   │   │   ├── kd_02_1af4.dll
│   │   │   ├── kd_02_10df.dll
│   │   │   ├── kd_02_10ec.dll
│   │   │   ├── kd_02_1137.dll
│   │   │   ├── kd_02_14e4.dll
│   │   │   ├── kd_02_15b3.dll
│   │   │   ├── kd_02_19a2.dll
│   │   │   ├── kd_02_1969.dll
│   │   │   ├── kd_02_8086.dll
│   │   │   ├── kd_07_1415.dll
│   │   │   ├── memtest.efi
│   │   │   ├── qps-ploc
│   │   │   │   └── memtest.efi.mui
│   │   │   ├── Resources
│   │   │   │   ├── bootres.dll
│   │   │   │   └── en-US
│   │   │   │       └── bootres.dll.mui
│   │   │   ├── updaterevokesipolicy.p7b
│   │   │   ├── winsipolicy.p7b
│   │   └── Recovery
│   │       ├── BCD
│   │       ├── BCD.LOG
│   │       ├── BCD.LOG1
│   │       └── BCD.LOG2

If you don't have such files, os-probe can't add them to Grub boot menu and start Windows.

To your partitions on sda and sdb you can look as / (root) or /home in linux analog. They are mounted after succesfull OS boot from ESP partition.

Offline

#21 2021-01-16 01:58:01

DigitalCyan
Member
Registered: 2021-01-13
Posts: 10

Re: [SOLVED] os-prober failing to locate Windows 10 after Arch reinstall

loqs wrote:
 1      1049kB  538MB   537MB   fat32                 boot, esp

The only ESP in the output.  DigitalCyan please read my edit to post 16.  You continue to contend Windows created an ESP on sda without explaining how you determined that or providing an explanation for why it is no longer present.

Yes, excuse my negligence. You are right. Just installed Win and it did target a pre-existing ESP.

GeorgeJP wrote:

To be able boot window you should have something similiar available on ESP partition (shortened)

You are right too.

lsblk -f
NAME        FSTYPE FSVER LABEL       UUID                                 FSAVAIL FSUSE% MOUNTPOINT
sda                                                                                      
|-sda1                                                                                   
`-sda2      ntfs                     82AA8F26AA8F15B7                                    
sdb                                                                                      
|-sdb1                                                                                   
`-sdb2      ntfs                     5E7486687486432F                                    
sdc                                                                                      
|-sdc1      ntfs         Windows USB 317048B975B5977A                                    
`-sdc2      vfat   FAT12 UEFI_NTFS   1DB0-EF13                                           
sr0                                                                                      
nvme0n1                                                                                  
|-nvme0n1p1 vfat   FAT32             6DFC-3A6B                             427.4M    16% /boot
|-nvme0n1p2 swap   1                 9f3bd583-66a4-4a93-9023-0250d5ab5db6                [SWAP]
`-nvme0n1p3 ext4   1.0               8990e5bd-f33c-45cc-80df-96e0dc3f7537    197G    10% /
ls /boot/EFI
Boot  GRUB  Microsoft

So if i wish to preserve the Win's boot files next time I happen to reinstall Arch, should I just move the Microsoft file over to my bootable device, install the OS and put it back? Would that work?

Offline

#22 2021-01-16 02:02:48

loqs
Member
Registered: 2014-03-06
Posts: 17,192

Re: [SOLVED] os-prober failing to locate Windows 10 after Arch reinstall

You do not need to move any files belonging to Windows.  They were removed because you formatted the ESP on the second installation of Arch.  Just omit formatting the ESP that is already in use.
If installing Windows overwrites the bootloader you setup using Arch reinstall that bootloader.

Offline

#23 2021-01-16 14:14:08

DigitalCyan
Member
Registered: 2021-01-13
Posts: 10

Re: [SOLVED] os-prober failing to locate Windows 10 after Arch reinstall

loqs wrote:

You do not need to move any files belonging to Windows.  They were removed because you formatted the ESP on the second installation of Arch.  Just omit formatting the ESP that is already in use.
If installing Windows overwrites the bootloader you setup using Arch reinstall that bootloader.

Actually a good point, thanks a bunch guys and thank you for your patience. Do I mark the thread solved now or by just changing the title to include [SOLVED]? I am really green when it comes to forums, this is was my first post.

Offline

#24 2021-01-16 14:20:41

2ManyDogs
Forum Moderator
Registered: 2012-01-15
Posts: 4,645

Re: [SOLVED] os-prober failing to locate Windows 10 after Arch reinstall

DigitalCyan wrote:

Do I mark the thread solved now or by just changing the title to include [SOLVED]? I am really green when it comes to forums, this is was my first post.

Edit your first post and add [SOLVED] to the title. Please read "How to Post" linked in my signature.


How to post. A sincere effort to use modest and proper language and grammar is a sign of respect toward the community.

Offline

Board footer

Powered by FluxBB