Windows 10 fails to boot, then it reboots, bizarre self-fix

I want to report an interesting event in my PC upgrade. Target machine was a Aspire, AMD A6 laptop running Windows 8.1, 32 bit mode, that I upgraded to Windows 10, 64x.

When Windows 10 came out in 2015 or so, I upgraded for free immediately, then, went back to Windows 8.1 but not before backing up the Windows 10 using Macrium. Then I forgot about this laptop, which is my girlfriend's anyway and she hardly uses it (preferring her smart phone).

I decided today to upgrade it back to Windows 10. So I used a USB hard drive to restore the Macrium image file from several years ago. Much to my disappointment, for unknown reasons, though I had plenty of HD space, the Macrium program said (something like): 'no more space on target' and exited with an error.

I tried to reboot to see if I could at least get Windows 8.1 and I got a blank screen. I waited a long time, even several hours, tried numerous things with the BIOS and still no luck. I even left it on overnight (by mistake) and still BSOD. The only thing I did not do is "load defaults" in BIOS but my settings were very generic, I checked them several times.

I decided to have to rebuy Windows 10. I found (I'm in the Philippines now) a cheap $10 version of Windows 10, proving Microsoft charges different prices depending on where you point of sale is, which I think is interesting, as Amazon (US) had a $99 price.

So I decided to use the Youtube tutorial below at [1] to use Rufus to load a Windows 10 ISO onto a USB stick, since this laptop has no CD/DVD. All was going well, I got Windows 10 loaded onto the USB following the tutorial below, after getting Windows 10 ISO downloaded from the Microsoft site.

Anyway, when I rebooted to USB, setting it to "UEFI" rather than "Legacy" (as Windows 10 apparently demands), I got a message that said (something like): "cannot boot to USB due to the security settings on this PC"

Again I played around with BIOS, setting UEFI to "Legacy" but nothing worked, blank screen, but no error message except 'Press any key, no bootable device found'. I tried booting another Windows 10 PC from the USB stick, and it recognized the stick. I checked the laptop USB ports and they had worked in the past (and, after fixing the problem as I explain below, they work now).

Out of desperation I simply left the PC on and unplugged the USB, after setting BIOS to 'default' settings. Then, after 10 minutes, I got a screen...and it was Windows 10 from several years ago! What a shock! Apparently the Macrium *did* restore the Windows 10 image file, despite the error, and apparently the Aspire laptop has a hidden file somewhere on the boot sector or otherwise that prevents anybody from booting to a USB stick?! I had set no security settings in the BIOS. The failure to boot from USB raises the question on how you would 'wipe clean' a HD to load another OS on it, say Linux, but I guess you can use that freeware "nuke" program from within Windows itself to reformat your HD? I don't care, as my problem is solved, but I'm just curious.

All's well that ends well, but it was bizarre. I've built many a PC from scratch back in the days but nowadays there's so many little tricks like this I wouldn't bother, I'd rather take it to Flasherly (or his equivalent here in PH) and I was going to do that just before the solution miraculously appeared.

RL

[1] https://www.youtube.com/watch?v=aJCkI14Lcd4 Windows 10 using USB stick