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I need to get back to Windows only, and after deleting the Ubuntu partition, GRUB shows up on boot. I can type exit to get into Windows but I don't want to do that every time I boot. I've been googling for about a day now and the conventional methods don't work for me. Help?

EDIT: I just ran efibootmgr on a Ubuntu 16.04 Live USB and it showed GRUB as the first option. I can't change it in my PC's BIOS because it 1. doesn't show the options 2. (extension of 1) it is really bad. Any help with efibootmgr to delete Ubuntu boot option would be appreciated as well.

PC Specs: i3 4005U 1.7 Ghz 4GB RAM 500GB HDD

3 Answers3

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In the past, I used a UEFI shell to remove a boot option (in my case though, it was to remove the pesky Windows bootmgr), but it should be the same process.

I usually use the Arch Linux installation medium to obtain a UEFI shell (I would use v2 so that you can use bcfg): https://www.archlinux.org/download/. Just boot into that disc and select the UEFI shell v2.

Then you would run the following commands:

Shell> bcfg boot dump -v
Shell> bcfg boot rm <number of the one you want to remove>

For more information on bcfg, the Arch Wiki has some: https://wiki.archlinux.org/index.php/Unified_Extensible_Firmware_Interface#bcfg

Hope this helps.

EDIT: Since the Arch Linux iso does not work, here are some steps to do it with a plain ol' USB stick.

  1. Since the shell in its current form is the issue (needs to be recompiled), I have recompiled it for you and you can download it here: http://downloads.markzz.com/shellx64_v2.efi
  2. Format a USB stick to FAT32 and make sure it has no files in it.
  3. Create the directory boot/efi on the usb stick.
  4. Move the shellx64_v2.efi file to the efi folder you created on the USB stick and rename it to shellx64.efi.
  5. Reboot the system and it should be in your boot options just like if you were booting an install disc.
markzz
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I recently made a dual boot (Windows 7, Xubuntu 16.04) on an Asus FX550JX and came across a solution to this (because I had some problems getting there). This is a bit of a "scorched earth" solution, but it worked (and that's knowing I had even managed to delete the EFI partition at some point ; and had reinstalled Ubuntu on the machine to fix the EFI).

BEFORE YOU DO THIS -->Backup your relevant data to an external hard drive.<-- (very important)

Make a Windows installer (a "live" CD/DVD or a USB stick you can find instructions on the Internet and if you can't find some, just ask). It depends on your machine, but you might want to avoid USB 3.0 for the install medium (Windows has some problems with it, at least it did for my Windows 7). Go into the BIOS and select the "boot override" option that corresponds to your live CD/USB prepped for installation. It will force your computer to boot with the install device rather than grub.

You should now be in the install menu of Windows "YourVersion" : now this is why you backed up your data : format every partition of your hard drive in this menu, and then let the software install Windows.

Normally grub should be gone and Windows be the only operating system on your machine. At least that's what had happened to me at that point in my adventures.

Good luck !

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Here is how you delete all entries in your boot options and restore Windows 10 boot with efi boot. With your Windows 10 usb in start computer press whatever function key (on my Dell it is F12) to get to the Boot Manager.

Select EFI USB

A warning comes up about a upgrade just click NO,

Windows Setup window comes up select NEXT,

Click on Repair your computer > Troubleshoot > Advanced Options > Command Prompt

Type in:

diskpart 
list disk
select disk 0 #(zero) Yours maybe different,
list volume #look for the SYSTEM FAT32 hidden usually 100MB (mine is Volume 3),
select volume 3 #whatever number yours is, maybe different change accordingly
format fs=fat32 quick label=System
list volume #look to see which Volume is Windows (mine is drive C) Remember it!
exit

At the command prompt type in bcdboot C:\Windows #Where your Windows drive was Type exit again

Click on Turn off computer, remove usb and restart. If your in doubt you can always hit the function key to look at the boot manager everything should be gone except Windows.