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How to boot back to Ubuntu within Windows by editing the Grub file when Grub Customizer is installed in Ubuntu?

hk flag
PManjunatha

I have a dual boot system with Windows and Ubuntu OS. Currently, Windows is the default OS. Within the Ubuntu environment, I use the Grub Customizer to change the order of OS. I have Linux File Systems for Windows by Paragon to read/write the Ubuntu partition. I went through multiple online solutions to change the Grub configuration file, but none of them worked in my case where Grub Customizer has been installed. Under Windows in the grub file, I changed GRUB_DEFAULT=0 to GRUB_DEFAULT=1, where 0 and 1 are the order of Windows and Ubuntu. But this did not boot back to Ubuntu. I noticed changing the order in the Grub Customizer did not change the GRUB_DEFAULT value in /etc/default/grub file.

How can I change back to Ubuntu from Windows by editing the Grub file when Grub Customizer is installed in Ubuntu? Below are the /etc/default/grub and /boot/grub/grub.cfg files:

# If you change this file, run 'update-grub' afterwards to update
# /boot/grub/grub.cfg.
# For full documentation of the options in this file, see:
#   info -f grub -n 'Simple configuration'

GRUB_DEFAULT="0"
GRUB_TIMEOUT_STYLE="hidden"
GRUB_TIMEOUT="10"
GRUB_DISTRIBUTOR="`lsb_release -i -s 2> /dev/null || echo Debian`"
GRUB_CMDLINE_LINUX_DEFAULT="quiet splash"
GRUB_CMDLINE_LINUX=""

# Uncomment to enable BadRAM filtering, modify to suit your needs
# This works with Linux (no patch required) and with any kernel that obtains
# the memory map information from GRUB (GNU Mach, kernel of FreeBSD ...)
#GRUB_BADRAM="0x01234567,0xfefefefe,0x89abcdef,0xefefefef"

# Uncomment to disable graphical terminal (grub-pc only)
#GRUB_TERMINAL="console"

# The resolution used on graphical terminal
# note that you can use only modes which your graphic card supports via VBE
# you can see them in real GRUB with the command `vbeinfo'
#GRUB_GFXMODE="640x480"

# Uncomment if you don't want GRUB to pass "root=UUID=xxx" parameter to Linux
#GRUB_DISABLE_LINUX_UUID="true"

# Uncomment to disable generation of recovery mode menu entries
#GRUB_DISABLE_RECOVERY="true"

# Uncomment to get a beep at grub start
#GRUB_INIT_TUNE="480 440 1"

grub.cfg file:

#
# 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 ###
if [ -s $prefix/grubenv ]; then
  set have_grubenv=true
  load_env
fi
if [ "${initrdfail}" = 2 ]; then
   set initrdfail=
elif [ "${initrdfail}" = 1 ]; then
   set next_entry="${prev_entry}"
   set prev_entry=
   save_env prev_entry
   if [ "${next_entry}" ]; then
      set initrdfail=2
   fi
fi
if [ "${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 initrdfail {
    if [ -n "${have_grubenv}" ]; then if [ -n "${partuuid}" ]; then
      if [ -z "${initrdfail}" ]; then
        set initrdfail=1
        if [ -n "${boot_once}" ]; then
          set prev_entry="${default}"
          save_env prev_entry
        fi
      fi
      save_env initrdfail
    fi; fi
}
function recordfail {
  set recordfail=1
  if [ -n "${have_grubenv}" ]; then if [ -z "${boot_once}" ]; then save_env recordfail; fi; fi
}
function load_video {
  if [ x$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  6bf5eb39-ee48-4b45-a2a7-38c91f2da948
else
  search --no-floppy --fs-uuid --set=root 6bf5eb39-ee48-4b45-a2a7-38c91f2da948
fi
    font="/usr/share/grub/unicode.pf2"
fi

if loadfont $font ; then
  set gfxmode=auto
  load_video
  insmod gfxterm
  set locale_dir=$prefix/locale
  set lang=en_US
  insmod gettext
fi
terminal_output gfxterm
if [ "${recordfail}" = 1 ] ; then
  set timeout=30
else
  if [ x$feature_timeout_style = xy ] ; then
    set timeout_style=hidden
    set timeout=10
  # Fallback hidden-timeout code in case the timeout_style feature is
  # unavailable.
  elif sleep --interruptible 10 ; then
    set timeout=0
  fi
fi
### END /etc/grub.d/00_header ###

### BEGIN /etc/grub.d/05_debian_theme ###
set menu_color_normal=white/black
set menu_color_highlight=black/light-gray
### END /etc/grub.d/05_debian_theme ###

### BEGIN /etc/grub.d/10_linux_proxy ###

function gfxmode {
    set gfxpayload="${1}"
    if [ "${1}" = "keep" ]; then
        set vt_handoff=vt.handoff=1
    else
        set vt_handoff=
    fi
}
if [ "${recordfail}" != 1 ]; then
  if [ -e ${prefix}/gfxblacklist.txt ]; then
    if hwmatch ${prefix}/gfxblacklist.txt 3; then
      if [ ${match} = 0 ]; then
        set linux_gfx_mode=keep
      else
        set linux_gfx_mode=text
      fi
    else
      set linux_gfx_mode=text
    fi
  else
    set linux_gfx_mode=keep
  fi
else
  set linux_gfx_mode=text
fi
export linux_gfx_mode



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

### BEGIN /etc/grub.d/30_os-prober_proxy ###
menuentry "Windows" --class windows --class os $menuentry_id_option 'osprober-efi-82B9-41CD' {
    insmod part_gpt
    insmod fat
    if [ x$feature_platform_search_hint = xy ]; then
      search --no-floppy --fs-uuid --set=root  82B9-41CD
    else
      search --no-floppy --fs-uuid --set=root 82B9-41CD
    fi
    chainloader /EFI/Microsoft/Boot/bootmgfw.efi
}
### END /etc/grub.d/30_os-prober_proxy ###

### BEGIN /etc/grub.d/31_linux_proxy ###
menuentry "Ubuntu" --class ubuntu --class gnu-linux --class gnu --class os $menuentry_id_option 'gnulinux-simple-6bf5eb39-ee48-4b45-a2a7-38c91f2da948' {
    recordfail
    load_video
    gfxmode $linux_gfx_mode
    insmod gzio
    if [ x$grub_platform = xxen ]; then insmod xzio; insmod lzopio; fi
    insmod part_gpt
    insmod ext2
    if [ x$feature_platform_search_hint = xy ]; then
      search --no-floppy --fs-uuid --set=root  6bf5eb39-ee48-4b45-a2a7-38c91f2da948
    else
      search --no-floppy --fs-uuid --set=root 6bf5eb39-ee48-4b45-a2a7-38c91f2da948
    fi
        linux   /boot/vmlinuz-5.4.0-97-generic root=UUID=6bf5eb39-ee48-4b45-a2a7-38c91f2da948 ro  quiet splash $vt_handoff
    initrd  /boot/initrd.img-5.4.0-97-generic
}
### END /etc/grub.d/31_linux_proxy ###

### BEGIN /etc/grub.d/33_linux_zfs ###
### END /etc/grub.d/33_linux_zfs ###

### BEGIN /etc/grub.d/36_linux_proxy ###
submenu "Advanced options for Ubuntu"{
menuentry "Ubuntu, with Linux 5.4.0-97-generic" --class ubuntu --class gnu-linux --class gnu --class os $menuentry_id_option 'gnulinux-5.4.0-97-generic-advanced-6bf5eb39-ee48-4b45-a2a7-38c91f2da948' {
        recordfail
        load_video
        gfxmode $linux_gfx_mode
        insmod gzio
        if [ x$grub_platform = xxen ]; then insmod xzio; insmod lzopio; fi
        insmod part_gpt
        insmod ext2
        if [ x$feature_platform_search_hint = xy ]; then
          search --no-floppy --fs-uuid --set=root  6bf5eb39-ee48-4b45-a2a7-38c91f2da948
        else
          search --no-floppy --fs-uuid --set=root 6bf5eb39-ee48-4b45-a2a7-38c91f2da948
        fi
        echo    'Loading Linux 5.4.0-97-generic ...'
            linux   /boot/vmlinuz-5.4.0-97-generic root=UUID=6bf5eb39-ee48-4b45-a2a7-38c91f2da948 ro  quiet splash $vt_handoff
        echo    'Loading initial ramdisk ...'
        initrd  /boot/initrd.img-5.4.0-97-generic
}
menuentry "Ubuntu, with Linux 5.4.0-97-generic (recovery mode)" --class ubuntu --class gnu-linux --class gnu --class os $menuentry_id_option 'gnulinux-5.4.0-97-generic-recovery-6bf5eb39-ee48-4b45-a2a7-38c91f2da948' {
        recordfail
        load_video
        insmod gzio
        if [ x$grub_platform = xxen ]; then insmod xzio; insmod lzopio; fi
        insmod part_gpt
        insmod ext2
        if [ x$feature_platform_search_hint = xy ]; then
          search --no-floppy --fs-uuid --set=root  6bf5eb39-ee48-4b45-a2a7-38c91f2da948
        else
          search --no-floppy --fs-uuid --set=root 6bf5eb39-ee48-4b45-a2a7-38c91f2da948
        fi
        echo    'Loading Linux 5.4.0-97-generic ...'
            linux   /boot/vmlinuz-5.4.0-97-generic root=UUID=6bf5eb39-ee48-4b45-a2a7-38c91f2da948 ro recovery nomodeset 
        echo    'Loading initial ramdisk ...'
        initrd  /boot/initrd.img-5.4.0-97-generic
}
menuentry "Ubuntu, with Linux 5.4.0-96-generic" --class ubuntu --class gnu-linux --class gnu --class os $menuentry_id_option 'gnulinux-5.4.0-96-generic-advanced-6bf5eb39-ee48-4b45-a2a7-38c91f2da948' {
        recordfail
        load_video
        gfxmode $linux_gfx_mode
        insmod gzio
        if [ x$grub_platform = xxen ]; then insmod xzio; insmod lzopio; fi
        insmod part_gpt
        insmod ext2
        if [ x$feature_platform_search_hint = xy ]; then
          search --no-floppy --fs-uuid --set=root  6bf5eb39-ee48-4b45-a2a7-38c91f2da948
        else
          search --no-floppy --fs-uuid --set=root 6bf5eb39-ee48-4b45-a2a7-38c91f2da948
        fi
        echo    'Loading Linux 5.4.0-96-generic ...'
            linux   /boot/vmlinuz-5.4.0-96-generic root=UUID=6bf5eb39-ee48-4b45-a2a7-38c91f2da948 ro  quiet splash $vt_handoff
        echo    'Loading initial ramdisk ...'
        initrd  /boot/initrd.img-5.4.0-96-generic
}
menuentry "Ubuntu, with Linux 5.4.0-96-generic (recovery mode)" --class ubuntu --class gnu-linux --class gnu --class os $menuentry_id_option 'gnulinux-5.4.0-96-generic-recovery-6bf5eb39-ee48-4b45-a2a7-38c91f2da948' {
        recordfail
        load_video
        insmod gzio
        if [ x$grub_platform = xxen ]; then insmod xzio; insmod lzopio; fi
        insmod part_gpt
        insmod ext2
        if [ x$feature_platform_search_hint = xy ]; then
          search --no-floppy --fs-uuid --set=root  6bf5eb39-ee48-4b45-a2a7-38c91f2da948
        else
          search --no-floppy --fs-uuid --set=root 6bf5eb39-ee48-4b45-a2a7-38c91f2da948
        fi
        echo    'Loading Linux 5.4.0-96-generic ...'
            linux   /boot/vmlinuz-5.4.0-96-generic root=UUID=6bf5eb39-ee48-4b45-a2a7-38c91f2da948 ro recovery nomodeset 
        echo    'Loading initial ramdisk ...'
        initrd  /boot/initrd.img-5.4.0-96-generic
}
}
### END /etc/grub.d/36_linux_proxy ###

### BEGIN /etc/grub.d/37_linux_xen ###

### END /etc/grub.d/37_linux_xen ###

### BEGIN /etc/grub.d/38_memtest86+ ###
### END /etc/grub.d/38_memtest86+ ###

### BEGIN /etc/grub.d/39_os-prober_proxy ###


set timeout_style=menu
if [ "${timeout}" = 0 ]; then
  set timeout=10
fi
### END /etc/grub.d/39_os-prober_proxy ###

### BEGIN /etc/grub.d/40_uefi-firmware ###
menuentry 'System setup' $menuentry_id_option 'uefi-firmware' {
    fwsetup
}
### END /etc/grub.d/40_uefi-firmware ###

### BEGIN /etc/grub.d/42_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/42_custom ###

### BEGIN /etc/grub.d/43_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/43_custom ###

Any help is much appreciated.

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hu flag
mikewhatever
You need to run `sudo update-grub` after editing the file. Can Windows do that?
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oldfred avatar
cn flag
oldfred
Grub Customizer replaces grub's files with its own proxy versions. You may need to totally reinstall grub to remove Customizer versions. Your grub.cfg is not complete, as if all scripts, now proxy scripts did not run. Please copy & paste the pastebin link to the Bootinfo summary report ( do not post report), do not run the auto fix till reviewed.Lets see details, use ppa version with your USB installer (2nd option) or any working install, not Boot-Repair ISO https://help.ubuntu.com/community/Boot-Repair
1
Reply
Score:1
Joepie Es avatar Ubuntu
eg flag
Joepie Es

If you would copy

menuentry "Ubuntu" --class ubuntu --class gnu-linux --class gnu --class os $menuentry_id_option 'gnulinux-simple-6bf5eb39-ee48-4b45-a2a7-38c91f2da948' { recordfail load_video gfxmode $linux_gfx_mode insmod gzio if [ x$grub_platform = xxen ]; then insmod xzio; insmod lzopio; fi insmod part_gpt insmod ext2 if [ x$feature_platform_search_hint = xy ]; then search --no-floppy --fs-uuid --set=root 6bf5eb39-ee48-4b45-a2a7-38c91f2da948 else search --no-floppy --fs-uuid --set=root 6bf5eb39-ee48-4b45-a2a7-38c91f2da948 fi linux /boot/vmlinuz-5.4.0-97-generic root=UUID=6bf5eb39-ee48-4b45-a2a7-38c91f2da948 ro quiet splash $vt_handoff initrd /boot/initrd.img-5.4.0-97-generic

which is located in ### BEGIN /etc/grub.d/31_linux_proxy ### in your 'grub.cfg' to ### BEGIN /etc/grub.d/10_linux_proxy ### at the end of what is already there, and save it like that ( make copy first and name it e.g. grub.cfg.bck ), you should boot into Ubuntu. Why? Because Ubuntu is mentioned above Windows ( 10 is lower than 30 (lower number is more important than higher number )).

As you use Windows I like to mention that there is a program called Grub2win, a grub which you can install in Windows. I use this myself ( triple boot Kubuntu, Mint and Windows 10 ) and set is as default bootloader. When I get Windows updates it prefends that the Windows bootloader takes over from grub ( the Linux one ). Saves me a lot of work after every Windows update.

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hk flag
PManjunatha
Joepie, thanks for your help. It worked like a charm! Sorry, I do not have enough reputation to upvote this solution.
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