You should also open your external hard drive in Windows Explorer and check to see what hidden files are stored in the root directory.

Read my post on how to change the boot order in Windows. Give the system a reboot and see if you’re stuck at the black screen or not. Make sure to move USB-HDD or USB all the way to the bottom. The boot order screen is usually somewhere on one of the advanced options pages, so you’ll have to browse around a little to find it. If USB somehow was moved up in the boot sequence, then you’ll also run into this problem whenever you connect any USB hard drive to your PC.

While you’re in the BIOS, you should also check the boot order. If Auto does not work, you can try Disable, but be cautioned that you’ll not be able to use your mouse/keyboard before Windows loads. The other thing you can try instead of disabling is to set it to Auto. Some people have suggested disabling it, but that also means you won’t be able to use a USB keyboard or mouse when the computer is booting up, which could be a problem if Windows stop loading one day and you have to navigate the DOS prompts. Another possible way to fix the issue is to go into the BIOS and adjust the settings for Legacy USB Support or USB Device Legacy Support.

How to format my hard drive from boot