I bought a brand new PC two months ago. In the meantime, I realized that my hard drive is a bit small. That was the main reason why I bought new SATA WD hard disk yesterday. When I plug it in my PC, everything worked fine at the beginning. However, my WD hard drive disappeared after reset. From that moment, my hard disk fails several times. I don't know what is the matter.
Open your PC and, check did you firmly connect all the cables. If that is OK, try to reconnect your hard disk to another SATA connector if you have any on your motherboard. Also, check does your motherboard support your type of SATA hard disk. I mean that your hard disk may be SATA2 and your motherboard may support only SATA1 disks. If that is the problem, then the only thing you could do is to replace your SATA2 disk with SATA1 disk. Do not forget to check in BIOS is your motherboard SATA support enabled. Before you give up, check in your motherboard manual does your motherboard maybe needs some drivers to be installed for full SATA support.