Newly installed UbuntuMATE 18-04 does not boot

[Bret Busby]

Hello.

I have just rebooted a computer after I (believe that I) installed
UbuntuMATE 18-04, on the computer that has MS Windows installed, and,
after the "Installation is complete. Reboot the computer" (or, words
to that effect), followed by the "Remove the installation media from
the DVD drive and press Return" (or, words to that effect, it booted
directly into MS Windows, as if Ubuntu had not been installed.

In using the MS Windows file manager, the C: drive size has been
changed, as intended, in the (believed) Ubuntu installation, but, no
GRUB boot manager or other bootloader screen (which would show the
presence of more than one operating system installation, being
present, apart from providing the option of which operating system to
boot) appeared, and it is as if the Ubuntu installation had not
happened (now, I am not confident that it did install).

In the installation process, in one screen, three options were displayed -
1. Install alongsside the Windows installation, using the Windows bootloader
2. Use the whole disk, eliminating the MS Windows installation
3.Other (this allows changing the disk partioning)

I used the third option, as I needed to repartition the HDD, and, from
memory, that was previously the option that installed and implemented
GRUB.

Now, no installation of Ubuntu Linux, is apparent.

This is on a UEFI/GPT system.

Please advise.

Thank you in anticipation.

-- 
Bret Busby
Armadale
West Australia
..............

"So once you do know what the question actually is,
 you'll know what the answer means."
- Deep Thought,
 Chapter 28 of Book 1 of
 "The Hitchhiker's Guide to the Galaxy:
 A Trilogy In Four Parts",
 written by Douglas Adams,
 published by Pan Books, 1992

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