Hi there 05ryan,
Even though it looks like that the cables are properly connected, they could be faulty.
This is why, as Barty1884 suggested, you can try using both different SATA and power cables. In case the issue persists, you can even attach the drive to another system, so you can be sure if there's something wrong with your system or the HDD itself. If it is not recognized over there as well, then there's something wrong with the drive and you will need to replace it.
Cheers,
D_Know_WD
