Maybe you don't have the USB drivers you need for Windows 10. I'd check that out. If you have a desktop (you didn't say), you could also buy an expansion card to add either more SATA or USB ports.
I'm confused. If it's an external HDD, why do you mention SATA ports? All external HDDs I've ever seen plug into USB ports.
It is the BLAC X Duet. You can use either Sata or USB. As I said I am out of Sata ports and it will not be recognized by any of my USB ports on WIN 10. On Win 8 & 8.1 it worked fine on USB.
Maybe you don't have the USB drivers you need for Windows 10. I'd check that out. If you have a desktop (you didn't say), you could also buy an expansion card to add either more SATA or USB ports.