As far as I know MBR support isn't required for UEFI.
Dell says they removed the "Legacy internal devices" Because new hardware doesnt even support old OS's so there was no need.
At a high level this makes sense, windows 7 doesn't support new 9th gen Intel CPU's etc. but in this case "Legacy" support would be great since it is a 10 OS from a legacy machine.
That is actually the first guide I followed.
Yeah I've done the conversion on a different computer with EaseUS Partition tool's and it still doesn't help me in adding it as a boot option on the UEFI only system.
I always have backups
I have a clone of my main drive that I'm using as the source for my conversions and extra clone mods.
ANYWAY, I WAS ABLE TO GET IT TO WORK BY DOING THE FOLLOWING:
1. On the new UEFI only system, I installed a blank drive and did a clean install of win 10.
2. I used THAT drive (from step 1) as the TARGET of a clone in Acronis, using my "orig" drive as the source.
3. I cloned in a way that doesn't copy the source partition scheme (MBR) and instead left it as-is (GPT, from when I did a clean install on it on the UEFI ONLY system)
(In doing that, Acronis says the target drive WON'T be bootable)
4. Installed my new cloned drive that isn't bootable into the new Dell UEFI ONLY system.
5. Found that indeed it isn't bootable
6. Booted from a Windows 10 flash drive and saw that it doesn't see any Win 10 installs on internal drives (by not having any "Continue to Windows 10" Option on the main repair screen.
7. Opened command prompt (from the USB Win 10 USB media) and browsed to c:\ d:\ e:\ and f:\... F:\ had the Users and Windows Dir
8. From F:\ I ran "bcdedit /rebuildbcd"
9. It found the Win 10 instalation and asked if I wanted to add it to the BCD file.
10. I said "Y" and prepared for it to say "we couldn't find the source or access it blah blah blah" like usual. BUT INSTEAD IT SAID IT WAS SUCCESSFUL! HOORAY I THOUGH.
11. After that successful command, I returned to the main repair screen from the Win 10 USB media
12. WE NOW HAVE AN OPTION THAT SAYS "Continue to Windows 10"
13. I excitedly select that option.
14. It reboots... AAAAAAAND ...loads right back into the USB media
hahaha
15. I try again and pull the flash drive out after it reboots and it boots right into UEFI, meaning that it was indeed booting of the flash drive and not the internal SSD.
16. I boot back off the Win 10 USB media for repair...
17. I run startup repair from the flash drive and BAM
WE NOW HAVE A BOOTING SYSTEM SSD THAT WORKS ON HER NEW UEFI ONLY LAPTOP AND HER OLD DESKTOP (when it's set to UEFI mode rather than "legacy")
HOORAY!
Thought I'd share with you guys as that was a very strange one for me.
-Dylan
