Question I installed Windows on HDD, it won't boot.

[PaPies]

FIXED WITH A TWIST.

 

[onespeedbiker]

I would go back to square one; a minimal install of Windows 10 is between 11GB and 19GB. Follow the instructions in this link https://forums.tomshardware.com/faq/how-to-do-a-clean-installation-of-windows-10.3170366/ and make sure you only have the target drive attached (unplug and/or detach any other drive except the USB installer. BTW, during the install, you can remove the USB installer after the first reboot and it certainly should not be plugged in when you are booting windows from your hard drive.