I agree on the USB issue hence the test. If the USB port works then we test the cable, then the hard drive compatibility and so forth.
Yeah, I agree with that. But if still having issues, I might uninstall the USB drivers, then reboot and let Windows re-install drivers and (fingers crossed) reset any corrupt setting.
For that matter, a cold restart (shutdown and power-off, then restart with no USB devices attached) could reset any Registry setting messing up your Windows Explorer settings. Have you rebooted with no drive attached yet? On some notebooks, you need to remove the battery too for it to really be off.
I am not sure I would try that drive via USB again, but rather installed
as a secondary - NOT boot drive in...