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I have Windows 10 HOME installed on my system. After I installed Windows 10 HOME, I installed Ubuntu 17.10 on a separate partition so that I could dual boot.

I removed Ubuntu 17.10 by deleting the partition it was installed on. Now I am unable to start my system. At boot, my system stops at the Grub command line.

I want to boot to my Windows 10 installation which I haven't removed from my system.

This is displayed at startup:

GNU GRUB version 2.02 ~beta3-4ubuntu7
minimal BASH-like editing is supported.for the first word, TAB lists possible commands completions.anywhere else TAB lists the possible device or file completion. grub>

How can I boot my Windows partition from this grub command? Laptop :- Toshiba satellite C55 - C5241

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  • 1
    This is a windows related question. utfg: how to repair boot in windows 10. Nov 21, 2017 at 7:00
  • Change the boot order in UEFI settings. It is currently set to grub. Set the first priority to Windows OS Manager.
    – defalt
    Nov 21, 2017 at 7:09
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    Idk this isn't totally unrelated as it involves the fact the OP installed Linux and thats why GRUB is there and GRUB is more likely to be familiar to Linux users.
    – jdwolf
    Nov 21, 2017 at 7:22
  • @IporSircer Well, I admit Windows support is not the most funny question to answer, but dualboot win/lin systems should be ontopic. I think the best strategy to deal with them would be to let the newbies to answer eachothers questions and not closing/downvoting them. If the longterm survival and expansion of the linux desktop is an important thing for us.
    – peterh
    Jan 9, 2018 at 1:59
  • Re-install Ubuntu and you'll get your boot prompts back. Then there are things you can do in Windows to remove GRUB (see this other question). Only after you've removed GRUB should you delete the Linux partition
    – Fox
    Jan 9, 2018 at 5:56

2 Answers 2

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GRUB uses the contents of /boot/grub/ located on your Linux partition to boot your system normally. Because of this GRUB has very minimal functionality.

If you are on a Legacy BIOS system you're out of luck and you'll need to Windows disk for boot repair. (this is because GRUB can't load its NTFS driver because you deleted it).

If you have a UEFI system which is most likely then you can still load Windows pretty easily.

First type:

chainloader +1

If this says unknown command you're out of luck because GRUB didn't embed this command so you must have deleted it.

If it reboots back to grub prompt then you have a legacy BIOS and you're out of luck.

If it says invalid efi path then you should be able to proceed.

Type:

ls (hd0,gpt1)/

this should return "/efi" Now do:

chainloader (hd0,gpt1)/EFI/Microsoft/Boot/bootmgfw.efi
boot
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    It's worth noting that GRUBs command line is super friendly especially its tab completion.
    – jdwolf
    Nov 21, 2017 at 7:40
  • Thanks. That helped, but i actually end up to command prompt menu. I tried to delete grub through command prompt but isn't working.
    – Hussain
    Nov 21, 2017 at 8:10
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    Why would you want to delete grub?
    – jdwolf
    Nov 21, 2017 at 8:57
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    This worked for me to be able to boot windows. But now everytime I restart the computer I need to write these commands. Any suggestion?
    – phdstudent
    Dec 11, 2019 at 22:59
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    @phdstudent It's off-topic to this site which is why it was closed. But I tried to answer in a way relevant to this one. If your goal is to keep Linux and GRUB bootloader what you want is to do is install os-prober for your distribution and then run 'update-grub' If your goal however is to restore your bootloader with Windows Boot Manager then you need to run 'bootrec /FixMbr' from Windows Recovery Environment.
    – jdwolf
    Dec 14, 2019 at 0:57
4

I solved a similar problem on this way:

  1. windows10+Ubuntu16 dual-system;
  2. I used MbrFix64 to change the booting from existed Ubuntun to Win10 in Win10 environment;
  3. And then, I was stupid followed delete all non-volume disks... this directly caused into the next trouble;
  4. restart the laptop, and stuck into grub> mode;
  5. Due to the existed ubuntu system been deleted, there are multiple (hd0, gptx) when act grub>ls; I try every disc, therefore the valid command is: grub> chainloader (hd0,gpt2)/EFI/Mcrosoft/Boot/bootmgfw.efi grub>boot
  6. it returned to Windows10 now.:-)

Lessons:

  1. should backup the important files and always prepare bootable dis/usb iso image on the side;
  2. Operating Mbrfix64 step is correct, but I should forget that my ubuntu booting files are in windows disc mixed probably;
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  • Please don't add "thank you" as an answer. Once you have sufficient reputation, you will be able to vote up questions and answers that you found helpful. - From Review
    – Jeff Schaller
    Jan 9, 2018 at 1:00
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    @JeffSchaller He started with a "thank you", but the content of his answer is imho an answer.
    – peterh
    Jan 9, 2018 at 1:54
  • Typically, "Thank you" means here voting up a post. :-)
    – peterh
    Jan 9, 2018 at 1:54
  • I'm not sure, but it seems to me that the crux of this answer (grub - chainloader hd0,gpt*/EFI/Microsoft/Boot/bootmgfw.efi) is the same as the existing answer
    – Jeff Schaller
    Jan 9, 2018 at 2:01

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