Computer Hardware Help → Multi-boot UEFI nightmare

Here's the problem:

I can't change UEFI default to go to grub instead of Windows bootloader.

Here's the situation:

I have a 10-partition GPT drive: sda.
sda1 is EFI partition.
sda2 is Linux Mint.
sda3 is windows recovery
sda4 is another EFI parttion that Windows 10 made when I installed it.
sda5 is "unknown" to gparted but apparently another partition Windows 10 took upon itself to make. (not boot, only flag is "msftres")
sda6 is the windows main partition
sda7 is a linux mountpoint (/home part)
sda8 is swap
sda9 is data
sda10 is ubuntu

When I boot up, after post, I go straight to Windows, no grub.

When I enter "boot menu" from post screen, optical drives are at the top of the list, then windows, then ubuntu. I can manually select ubuntu and get to grub menu. From grub, I can successfully boot to ubuntu, mint, or windows.

I want to see the grub menu by default, but I can't get there unless I press F11 on mobo post and select manually.

Mobo is several year old Intel. Has UEFI support, but limited customization. No SecureBoot setting. I can't find anything in BIOS menu to change boot order, only change optical/usb/HDD/network, but not the granularity to select partitions.

It's also weird because I used to have debian installed as well, but deleted it. However, debian is still in F11 "boot menu". I mounted sda1/, deleted EFI/debian directory, but it's _still_ there is the mobo boot menu. Where is it finding it? Selecting debian does nothing, only moves highlighted selection back to top of menu.

How do I get around this and get to grub menu by default, and not boot directly into Windows?

Ok, which was the last OS installed? If it was one of the *nix distro's, what option did you choose for the location of the grub boot loader?

Do you currently have only Windows 10 installed and none of the earlier versions?

UbuntuThe Ubuntu installer recognized sda1 and sda4 as efi partitions. I made no manual selection for configuring grub.Yes. And I've never installed any other Windows on this drive.

There is a software tool for Windows 7 and 8 but I don't know if it will work in Win 10 as win 10 is only in a preview mode for now. The tool is called BCDEDIT and it must be installed and configured from within a windows OS. This tool allows configuration of the boot order and will also display the boot menu and allow you to choose which OS to boot up, similar to GRUB.

BCDEDIT help. »www.sevenforums.com/tuto ··· use.html

Yea, you should try BCDEDIT like aguen was saying. I have a laptop that has Windows XP, Windows 7 dual boot. I installed Windows 8.1 because I got a copy and it changed my bootloader that everytime the computer would start it would load the Windows 8 boot, then give me a colorful GUI interface to choose an earlier version of windows or windows 7, force the computer to reboot again and load the different OS. Everytime I had to restart from XP or Windows 7 I wuold be stuck in that loop process.

I used EasyBCD and changed my bootloader & order and names so that now when my computer boots up I get the legacy black/white screen that lets me select O/S, issue F8 commands from the highlight prompt and load Windows. I was not able to do this with the Windows 8 GUI loader. It totally screws up a lot of things, I heard of even deleting bootloaders for some to previous OS'es. I wouldn't doubt in my mind that Windows 10 runs the same way as Windows 8 and corrupts the boot.

I would follow the 7 forums link on BCDEDIT or try EASYBCD software run from Windows like aguen said. You might be able to configure it all there and setup the way you like it. Though you have so many mixed OS'es from Linux to Ubuntu might not guarantee anything but worth a shot.