USB hard drive not detected by W10

[Elodie CEMOI]

I have upgraded to W10-64 pro yesterday, and everything is OK except that my USB-3 Hard drive are not detected.

The USB sticks are detected (USB 2 or 3), but not the hard disks...

No error or exclamation marks in the device Manager.

How can I fix it ?

My PC:
Asus Z87-Pro C2 with 32Gb
Bios 1602
i7-4770K

 

[bassfisher6522]

Are you using the legacy BIOS or the new UEFI? If the UEFI, try disabling it and using just BIOS. Then check disk management and see if it's showing up in there, if so does it have an assigned drive letter attached to it.

 

[Elodie CEMOI]

I use the UEFI Bios : how can I disable it ??
At startup I get the "DEL or F2" option to enter in the BIOS setup, but I see no way to disable the UEFI ??
Thank you for your help,