First time builder: I can't get windows 10 (USB) to install on ASRock B250 Pro4 motherboard

[x_Code89]

I have made sure to select the USB as the boot mode. When I do that, nothing happens. The UEFI also shows up as my Windows USB and when I select that as my boot mode, I see a loading bar that says "loading files" and then I get a blue screen saying there was a problem and my computer will be restarted. The error code is:

0xc000021a

I've researched that, but I can't figure out how to manually boot from the USB so I can troubleshoot/repair my computer.

Any advice is welcomed.

 

[Bo Lee]

It is a corrupt file on the USB disc, possibly the USB disc itself bad.

Here is something from Microsoft that might help.
https://answers.microsoft.com/en-us/windows/forum/windows_8-update/error-0xc000021a-while-booting-from-usb/9a2fb4d7-8f32-422b-848b-a2b5b6f16c85

 

[Calvin7]

The sounds like all you have is an ISO image of Windows 10 on a USB. You need to search on Google for "How to create bootable USB media from ISO for Windows 10".