Asrock Extreme 4 has:
2 x Rear USB 3.0 ports by Intel® Z77, support USB 1.0/2.0/3.0 up to 5Gb/s
- 2 x Rear USB 3.0 ports by ASMedia ASM1042, support USB 1.0/2.0/3.0 up to 5Gb/s
- 1 x Front USB 3.0 header by Intel® Z77 (supports 2 USB 3.0 ports), supports USB 1.0/2.0/3.0 up to 5Gb/s
So 2 of them use a different driver and may have separate BIOS settings enabling them. Download the latest from Asrock website.
On yours where only one is not working, that probably leans toward a port failure at the hardware level. But where your friends is both back ports, I'd lean toward what I said above.
Okay so basically update the BIOS?