Windows 10: Deleted ubuntu from partition but still got ubuntu boot option when i boot from boot menu f12

Hello,One year + ago I installed ubuntu as a dual boot with windows. I've since then deleted the partition of the ubuntu because I didn't need the dual boot anymore.In the disk management I believe there is no partition of ubuntu. When I boot up from boot menu f12 I still got the option boot in/from ubuntu. How is this possible and how do I completely remove ubuntu?

:)

 

Dual boot with Ubuntu

Are you booting from a Grub loader or from the win loader? It will not delete the Ubuntu partition or data but you may have to re-install the loader if it is Grub/Ubuntu

 

Help with dual booting Win 10 and Ubuntu

My suggestion is to set HDD (Ubuntu) as BIOS first boot option . Under grub you select Ubuntu or Windows.
Remove the Ubuntu option under Windows boot manager.

I use the boot menu (F12 on my MB) to choose Lubuntu and have disabled Windows on Grub boot manager.

 

Help with dual booting Win 10 and Ubuntu

I tried the suggestion from @topgundcp and here are my findings:

To recap: I have Windows 10 on an SSD in a DVD caddy (/dev/sdb)... Ubuntu mate on an HDD (/dev/sda). Both are Legacy BIOS/MBR on a Dell Laptop.

I didn't do anything to Win 10.

In Ubuntu on the HDD I ran these commands:
Code:

Then I booted back in to Windows and ran EasyBCD to update the boot manager menu to add Linux to it pointing to the linux root partition where I installed GRUB2 above (/dev/sda5). I chose sda5 because that is the Ubuntu root partition.

I didn't "re-initialise" the disk. I think that means to reformat and do a fresh Ubuntu install. Maybe I should have because now...

1. If I let it boot as normal it boots in to the GRUB2 menu and I can choose Ubuntu or Windows. With my BIOS I can only default boot to /dev/sda where Ubuntu is installed. For /dev/sdb I need to press F12 and chose it from the one-time boot menu.
2. If I hit F12 on boot up and boot from the DVD drive, now I get the fancy Windows metro dual boot screen and can choose Windows or Ubuntu. If I chose Windows it loads Windows. If I choose Ubuntu..................... it reboots, then I get the Grub2 menu.

Is this the expected outcome? I thought that choosing Ubuntu from the Windows boot manager screen would just immediately load Ubuntu? I thought that was one of the benefits of @topgundcp suggestion to put GRUB2 on a Linux partition rather than in /dev/sda.

Or do I need to do a fresh reinstall of Ubuntu to ensure "there's nothing remained in the MBR". Can that be done without a complete Ubuntu re-install?

Maybe it's because there are two OS's on the GRUB2 menu - Windows 10 an Ubuntu? If I delete Windows from there maybe then Windows bootmgr will just load Ubuntu without having to do an extra reboot?

Cheers,

Flex