Haha, nah, I am at 'all suggestions gratefully received' before new ssd and a win 10 recovery flash drive arrive tomorrow. (It recognises my current flash drive but not the win 10 iso I downloaded via phone on it.)
No USB devices attached returns same failure to boot. Likewise trying solely boot drive attached. CMOS has been reset, and recognised in bios, too.
Sounds like your OS is corrupt. All hardware is being detected so it looks to be software related.
Is UEFI enabled in bios?
You can access the advanced start up menu by forcing the machine to shut down 3 times when it boots. Once in the menu, select troubleshoot then advanced options, look for command prompt. Run the command "sfc /scannow" - this will scan your OS for any discrepancies and fix accordingly.
Other things you can try - when in the advanced start up menu, select troubleshoot then advanced options, select uninstall updates, remove the feature update / latest quality update. Try to boot again.
when in the advanced start up menu, select troubleshoot then advanced options, run start up repair.
If that fails, access advanced start up menu again, select troubleshoot then advanced options, select startup settings then restart. You will be given a choice of options to select from, try booting to safe mode w/ networking by pressing "5" i believe.
If that also fails, access the same menu as before (safe mode etc), but this time select disable driver signature enforcement. Try to reboot.
Hopefully one of those work. If not, id dock the hard drive an pull any important data (though, any important data should be on the cloud already!!
) and reinstall the OS.