I think you will find it's there but simply isn't yet recognized by the OS 
If you right click "computer" and select "manage" then goto "disk management" hopefully your drive will be there and all you need to do is right click it and assign a drive letter 
If you want it to be "D" then first reassign the CD drive. To do this simply right click the disk drive that is currently "D" and by following "change drive letter and paths" and changing that to something else such as "E" then "D" will become available as an assignable drive letter 
let us know how you get on
Trust me I'm a teenagers father!

Operating System Windows7, vista, xp, snow leopard
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CPU Type and Speed AMD Phenom II 940 Black Edition
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