new harddrive issue

[StriderZ]

ok so after i was copying my WoW folder from 1 computer to another(this one has the new hd), after it finish copying a msg popped up saying "cannot copy FILE: The device is not ready", and i went to my computer and the new harddrive drive is gone?!, i then went to control panel > admin tools > computer management and clicked disk management on the left and it also can't find the harddrive, but when i restart my computer i can see it again(and if i try to copy the WoW folder again same thing happens)..anyone know what's wrong?

 

[SinxarKnights]

Could be defective. That is exactly what mine did when I first got it. Mine got to the point that it wouldnt even show up in the BIOS.