Hi
PCNetSpec,
Sorry for the late reply but I was out of town for a short while.
Thanks again for your time and effort. It is most probably true that back when I bought this laptop
Win8 was typically installed by default. But when I purchased this laptop I purchased it precisely because the dealer could deliver it
without any OS (although it turned out to have a pretty much useless and specked-down
Linux of some sort -- whose name I no longer remember -- and I immediately installed
PeppermintOS and eliminated the original from the HDD).
Unfortunately, the two videos that you found only show and describe what I have been doing all along. As an alternative I decided to try several other
Linux distros to see if the same problem occurs. With two
Ubuntus (
minimal and
Xubuntu) and with an
Arch derivative that uses the
Calamares installer the exact same thing occurs (
no EFI partition found error).
I was about to give up and either try installing the
Boot Repair utility or try performing the suggestion from
pin (moving the
boot flag to my
Peppermint 7 partition, installing
GRUB to the
MBR from there and then checking whether I could boot into the
Peppermint Ten installation).
But then I thought I would try one last distro and DL'ed
MX Linux 18.3. And
presto! No problem, it installed without hesitation and runs perfectly.

So I guess I'll mark this as
ABANDONED and fool around with
MX Linux for a bit (when I am not in
Peppermint Ten on my other machines).
Thanks again for the time and effort from yourself and
pin. I'm sorry it didn't really help us in any way WRT others having this problem (but until now, no one else has mentioned it as being an issue

).
Regards,
-- Slim