Moved HDD with Windows 10 back from another PC, doesn't boot

[Catishcat]

I know that that wasn't possible even on Windows 7, but heard that Windows 10 is much better at dealing with massive hardware changes (basically bringing it to another PC).

I moved my HDD to a different computer built out of random parts I found in my house, and Windows booted normally after "Getting devices ready" for a little while. Worked absolutely fine, even my background saved.

However, when I moved it back to my regular PC, it failed to boot because 0xc000000f (not counting about three first times it didn't start because I didn't install RAM properly...) Doesn't even work in Safe Mode, sadly.

So moving Windows 10 to another computer is okay, but taking it back somehow messes it up? xD What do I do without a clean install? I kinda don't want to lose my meme folder...

 

[Colif]

The problem is that the bios isn't finding the boot config data on the hdd, its likely the bios is looking in the wrong place. Its not windows this time, more a boot mix up. You could try swapping boot method in bios and see if it finds it again (is there a choice in bios called windows Boot Manager?)

See if these steps help - https://www.lifewire.com/how-to-rebuild-the-bcd-in-windows-2624508 - you can access the cmd menu using a win 10 installer as boot drive (On another PC, download the Windows 10 media creation tool and use it to make a win 10 installer on USB)

change boot order so USB is first, hdd second
boot from installer
on screen after languages, choose repair this pc, not install.
choose troubleshoot
choose advanced
choose command prompt
follow link above

 

[Catishcat]

The problem is that the bios isn't finding the boot config data on the hdd, its likely the bios is looking in the wrong place. Its not windows this time, more a boot mix up. You could try swapping boot method in bios and see if it finds it again (is there a choice in bios called windows Boot Manager?)

See if these steps help - https://www.lifewire.com/how-to-rebuild-the-bcd-in-windows-2624508 - you can access the cmd menu using a win 10 installer as boot drive (On another PC, download the Windows 10 media creation tool and use it to make a win 10 installer on USB)

change boot order so USB is first, hdd second
boot from installer
on screen after languages, choose repair this pc, not install.
choose troubleshoot
choose advanced
choose command prompt
follow link above

Sorry, forgot to answer after I solved everything.

I tried to boot from my Win10 installer DVD and it didn't even boot like that. After tinkering with it for what felt like an eternity (more like 3 hours), I found out that, apparently, I still somehow managed to poorly install the RAM! BIOS only recognized 3GB when I have 6. I finally put everything back, tried to boot, didn't work, but finally let me into the automatic restore screen. I ended up using the command prompt and, since I already had experience with my quirky PC, just typed in two commands: cd c: and dir... (so it WAS a boot mix up)

And then it booted into Windows, although it had to go through the whole "Getting devices ready" thing. Not sure if all of this was caused JUST by the RAM, but idk.

In more usual situations, your solution would probably be better.